Medium-range Soviet ballistic missile RSD-10 Pioneer (NATO name SS-20 Saber)
Soviet medium-range RSD-10 Pioneer missile (NATO name SS-20 Saber), withdrawn from service under INF Treaty; on display at outdoor museum in Ukraine.

After the INF Treaty: An Objective Look at US and Russian Compliance, Plus a New Arms Control Regime

December 07, 2017
Kevin Ryan

What if the 1987 INF Treaty cannot be saved? Russia, according to U.S. officials, has been in violation of the treaty since at least 2014. The U.S. is on the verge of violating, if it has not already done so. It is only a matter of time before the treaty collapses. When it does and Russia and the United States openly begin building medium-range ground-launched missiles again, we could see the resumption of the 1980s arms race that was arguably the most dangerous time in European security. Or it could be an opportunity to start a new chapter in nuclear arms talks. This article examines briefly why the 1987 INF Treaty will collapse and how the two sides can nevertheless achieve the treaty's main goal of preventing a sudden regional nuclear war in Europe: by creating a new treaty focused not on delivery systems but on their non-strategic nuclear warheads.

The Collapse of the INF Treaty

Soon after the United States withdrew from the Anti-Ballistic Missile (ABM) Treaty in June 2002, Russian leadership began suggesting that Russia might in turn withdraw from the 1987 Intermediate-Range Nuclear Forces (INF) Treaty, which prohibits the U.S. and Russia from testing or deploying ground-based missile systems with a range between 500 and 5,500 km. The principal reason for Russia's position is a perceived gap between Russian and Western (mainly American) military power in the European theater. That perception, by Russia, of being behind is similar to what prompted Moscow in the 1970s to develop and deploy modernized medium-range nuclear missiles like the SS-201 throughout the western USSR and Eastern Europe.2 The missile had a range of over 5,000 km and could deliver up to three nuclear warheads with an accuracy to within 450 meters. That Cold War decision led to a counter-deployment of Pershing and cruise missiles by the United States and ultimately to the 1987 INF Treaty banning all such missiles in the two countries.3

Over the past 30 years, the achievement of the INF Treaty—reducing the risk of a sudden nuclear attack in the European theater—has been gradually eroded by new technologies and changing threats. Today, modern drones can deliver nuclear weapons in the 500-5,500-kilometer range. Air- and sea-launched cruise missiles, not covered by the treaty, are proliferating and can deliver nuclear warheads over much of the European region that the treaty hoped to protect. New threats, such as the increase in shorter- and intermediate-range missiles among third states (North Korea, Iran and Pakistan), have prompted military strategists in Russia and the U.S. to argue for balancing capabilities.

In the case of the United States, advanced ballistic missile defenses have been developed and deployed in Europe, Asia, the Middle East and on sea.4 The desire to hit terrorist cells far from U.S. bases (like in Afghanistan), rapidly and on short notice, prompted then-Defense Secretary Donald Rumsfeld to explore transitioning selected submarine-launched nuclear ballistic missiles to conventional warheads—a workaround necessary because of the lack of medium-range ground-based systems among other things.5

These new technologies and threats, plus the post-Cold War shift in Europe’s strategic balance toward NATO, have led Russia to pursue its own solutions. According to U.S. officials, Russia has moved dangerously close to scuttling the INF Treaty by developing, testing and deploying a new cruise missile system (identified by U.S. sources as SSC-8) with a range that violates the treaty. The 2014, 2015, 2016 and 2017 Department of State reports titled “Adherence to and Compliance with Arms Control, Nonproliferation and Disarmament Agreements and Commitments” all declared that the United States has determined that “the Russian Federation is in violation of its obligations under the INF Treaty not to possess, produce, or flight-test a ground-launched cruise missile (GLCM) with a range capability of 500 km to 5,500 km, or to possess or produce launchers of such missiles.” According to a February 2017 New York Times article, the Russians have converted their ship-launched Kalibr cruise missile for ground launch.

Russia denies the allegations and makes its own allegations that the U.S. is violating the INF Treaty through its testing of rocket boosters and use of drones. Russian analysts also accuse the U.S. of deploying its own ship-based cruise-missile launcher onto land. They argue that the MK41VLS launcher in the Aegis Ashore missile defense system deployed in Romania—a launcher whose ship-borne version is designed to fire both Tomahawk cruise missiles and SM-3 interceptors—gives the U.S. the ability to launch intermediate-range cruise missiles from land. The U.S. maintains that the launchers ashore cannot fire the Tomahawk because, among other things, they would require software changes. Russia is not convinced. (See a further discussion of U.S. and Russian INF complaints in addendum.)

In response to Russia's alleged violation, some elected officials in the United States are setting the stage for withdrawal from the treaty. In the 2018 national defense budget bill, Congress has authorized the Department of Defense to spend $58 million to establish “a research and development program for a dual-capable road-mobile ground-launched missile system with a maximum range of 5,500 km.”6 This step is intended to avoid violating the letter of the INF Treaty by refraining from testing or deploying the missiles. But an argument could be made that it would violate the treaty if the development process meant simply "having" such missiles.7 Russian ambassador to the United States Anatoly Antonov is already calling such legislation "the first step of violation of the soul of the treaty. … For us, this is an indication that activities to create a new missile violating the treaty are going on."8

Even more provocatively, in the same budget, Congress has directed the DoD to report on the cost to convert existing missile systems, such as the missile-defense interceptor SM-3 currently deployed in Romania, into medium-range nuclear systems.9 Russian analysts will see this initiative as validation of their concern (noted above) that the ground-based missile-defense systems being deployed in Europe can also be used for intermediate range offensive missiles.

What American officials view as Russia's unapologetic violation of the treaty, together with escalating U.S. responses, makes it likely that one side or the other will suspend participation in the agreement and eventually withdraw. At the October 2017 Valdai Club meeting Russian President Vladimir Putin said: "If someone … wishes to withdraw from the treaty, for example, our American partners, our response would be … immediate and reciprocal." Deployments of medium-range ground-launched missiles would undoubtedly follow in the European theater.

The Coming Crisis

It is perhaps hard for many people today to appreciate the crisis that will ensue from nuclear-tipped medium-range missiles in the European theater. During the last such deployments in the 1980s, Europe lived under the umbrella of hundreds of U.S. (about 800) and Russian (about 1,800) medium- and short-range nuclear-tipped missiles (over 2,600 were destroyed under INF Treaty). These challenges will be new to most people. Almost half of today's American population was not born at the time of the 1987 treaty.10 None of the nearly 1.2 million active-duty service members, except for the senior generals and sergeants major, are old enough to have served in the military when the 1987 INF Treaty was signed.11

During the Cold War, the West and East had developed a strategic balance in Europe consisting primarily of conventional forces backed with battlefield (non-strategic) nuclear weapons. Both sides, U.S./NATO and USSR/Warsaw Pact, had an abundance of non-strategic nuclear weapons deployed in the European theater and had full intention to use them in case of war. (For example, when Russian ground forces prepared to leave Berlin after the 1990 German reunification, the senior Russian commander in Berlin asked for radiation meters from his American counterpart to sweep vacated ammunition storage sites in the Soviet sector of the city12—presumably to ensure that no traces of nuclear warheads remained.)

But the 1970s replacement of older SS-4 and SS-5 nuclear-tipped ballistic missiles with a larger number of multi-warhead SS-20 missiles, together with the 1980s U.S. deployment of Pershing II and cruise missiles, created an unstable situation in which either side could strike major cities, as well as military bases throughout the European region, with greatly improved accuracy in under 10 minutes. It was this increased capacity for a sudden nuclear strike anywhere in Europe (including European Russia) that destabilized security and created an arms race, which in turn brought negotiators to the table to find a solution.

Delivery Systems Versus Warheads

Throughout the 1980s INF negotiations, U.S. and Russian officials tabled several ideas to reduce the threat from non-strategic nuclear systems in Europe: combining negotiations on strategic and non-strategic nuclear weapons, capping the numbers of intermediate-range missiles, relocating missile systems, multilateralizing the treaty and others.13 In the end, negotiators agreed to a bilateral treaty that would eliminate the threat entirely. But they did this by eliminating the delivery systems and not the nuclear warheads themselves.

This decision is reflected throughout the treaty documents. First, the actual name of the agreement is “Treaty Between the United States of America and the Union of Soviet Socialist Republics on the Elimination of Their Intermediate-Range and Shorter-Range Missiles.”14 Nuclear warheads are not mentioned in the treaty’s text except to say they are not subject to destruction; the focus of the treaty is on the missile, not the warheads. Nevertheless, the intent of the treaty is to mitigate specifically a sudden strike with non-strategic nuclear warheads, making the informal U.S. title, “Intermediate-Range Nuclear Forces Treaty,” more reflective of the actual goal.

In 1987, eliminating the ground-launched delivery systems was an effective way to reduce the risk of a sudden nuclear attack. There were few other means of delivering the nuclear warheads quickly to a depth of 500-5,500 km. Both sides retained the desired ability to use non-strategic nuclear weapons for deterrence and planning (bombers and sea-launched warheads for example), but destroying the ground-based ballistic and cruise missiles (along with launchers and control systems) essentially guaranteed that the nuclear warheads would not be used in a sudden attack. In today's world of expanded technologies and nuclear-weapon states, however, that guarantee is far less certain. After the 1987 INF Treaty has been abandoned and both sides have resumed deploying shorter- and intermediate-range ground-launched missiles, the guarantee will be even weaker.

A New Arms Control Agreement

Even if both the U.S. and Russia renewed production of shorter- and medium-range ground-launched missiles, however, it would still be possible to achieve the original goal of the INF Treaty by flipping the focus of new arms talks. Instead of trying to roll back the deployment of delivery systems, a new agreement should focus on the nuclear warheads for these shorter- and intermediate-range systems. Russia and the U.S. rely on non-strategic nuclear weapons to deter the other from attack, but it is the sudden (preemptive or first-strike) nuclear attack that is most destabilizing. Storing the nuclear warheads apart from the delivery systems would be the key to reducing the risk of a sudden nuclear attack in Europe.

Reducing the risk of a sudden nuclear strike does not require destroying nuclear warheads, although such destruction/reduction of non-strategic nuclear weapons could be part of a broader follow-on agreement. If non-strategic nuclear warheads could be verifiably separated from the shorter- and intermediate-range delivery systems, both sides would feel confident that a sudden nuclear attack is not possible. A new treaty would have to provide confidence that chances for a "breakout" to mate nuclear warheads would be minimized. But, in a world where both sides have already deployed missiles (i.e., in a world after the 1987 INF Treaty), some level of breakout risk will always exist. What is an acceptable delay or warning period? Any amount of verifiable time would be better than having the warheads mounted on their delivery systems, but a good goal would be a day separation by ground transportation (a couple of hours by aircraft).

The verification regime for such a treaty presents perhaps the biggest hurdle. The 1987 INF Treaty itself was groundbreaking in its verification and access to delivery systems.15 This new treaty would focus on controlling the warheads rather than the delivery systems, and this may actually simplify the task. The new treaty would not have to concern itself with the changing locations or numbers of missile systems, which vary based on training, maintenance and operational deployments. Used with conventional warheads, these missiles can counter certain threats without threatening nuclear war. The U.S. and Russia would be free to build and deploy as many of these missile systems as they felt were needed and affordable. The new treaty would focus instead on the location of the nuclear warheads, which normally are stored in a secure storage site that does not move. Both sides are sensitive about revealing locations and movement of nuclear materials and warheads, but both sides have experience allowing for outside observation from previous agreements like those under the Cooperative Threat Reduction program. This arrangement would not affect intercontinental ballistic missiles with their nuclear warheads, so the strategic nuclear balance between the U.S. and Russia could remain outside any inspections under this new treaty.

A new treaty would be the first step toward declaring and controlling non-strategic nuclear warheads. The goal of the new treaty would not be to prevent the use of non-strategic nuclear warheads, but to provide adequate warning of their use. Neither side would feel secure in giving up the freedom to use these weapons, but both sides would be eager to avoid a first strike by the other. The treaty should focus on the European theater because it is there that non-strategic nuclear weapons pose the greatest risk to U.S. and allies' interests. As noted above, the treaty does not have to track the location of missile systems—only the location of non-strategic nuclear warheads with respect to those systems. Like the 1987 treaty, the new agreement should be bilateral between the U.S. and Russia and it should not be complicated by linking with strategic arms talks. Unlike the 1987 treaty, the new deal should include new systems: missile-defense interceptors, drones and air-launched systems (cruise missiles)—any shorter- or intermediate-range delivery systems capable of delivering a nuclear warhead in the European theater on short notice. (Ship-launched systems should be exempted from the requirement to separate their nuclear warheads as this is impractical and largely unverifiable.)

There are of course many obstacles to conducting new arms talks. Up to now, neither country has been willing to focus nuclear arms talks on warheads, especially non-strategic warheads. A toxic relationship between the two countries, particularly since the annexation of Crimea, has made it seem impossible for the two sides to find common ground. In fact, the divisions between the U.S. and Russia had been building since well before Crimea: Georgian sovereignty, missile-defense deployments, the Magnitsky sanctions and other thorny issues. In the United States, Congress has taken the lead in confronting Russia, complicating any executive branch initiatives. Russia, for its part, denies responsibility for the current situation while modernizing its military and threatening the use of non-strategic nuclear weapons. It would seem unlikely that new arms control initiatives could be initiated.

But one must remember that the 1987 INF Treaty was negotiated at a time that was equally, if not more, contentious. In the 1980s, on top of the precarious nuclear standoff in Europe, there were numerous political, religious and peace movements (Greens, Campaign for Nuclear Disarmament and others) and terrorist groups (Red Brigade, Red Army Faction, plus more) whose activities added to the instability in European security. It was a decade of conventional, nuclear, informational and asymmetric threats worthy of today's “hybrid” theorists.

The security situation in Europe today is dangerous: the illegal annexation of Crimea, fighting in eastern Ukraine, land grabs in Georgia, cyberattacks against the West, to name but a few of the challenges. Even so, it has not reached a level that would force the sides to reconcile. To bring the sides to the negotiating table will require a crisis situation such as led to the 1987 INF Treaty. The collapse of the 1987 treaty and subsequent deployments of nuclear-capable medium-range missiles would be just such a crisis.


The 1987 INF Treaty attempted to eliminate a threat by prohibiting the sides from developing and deploying certain kinds of offensive missile systems, much like the ABM Treaty attempted to prevent development and deployment of missile-defense systems. These agreements proved brittle under the pressure of new technologies and threats. Many in the U.S. and Russia have come to believe that their best interests are served by possessing these once-banned systems. The ABM Treaty was abandoned in 2002 and the INF Treaty will be next. But Russia and the United States, and Europe, can avoid the principal risks from a buildup of these medium-range systems by keeping them conventional and creating a verifiable delay/warning period before the systems can be mated with nuclear warheads. Transitioning from the control of delivery systems to the control of warheads will allow the two sides to pursue conventional medium-range systems that serve their security interests. At the same time the two sides can begin the process of bringing under control non-strategic warheads, the missing jewel of nuclear arms control.

Addendum: Discussion of US and Russian INF Treaty Complaints

Bottom Line Up Front

If press reports about the Russian ground-launched cruise missile development are accurate, it would seem that both the United States and Russia have transitioned their sea-based capability for intermediate-range missiles to land. The major difference is that Russia appears to have already tested its system and deployed it for land attack, whereas the U.S. has a latent capability that is unintended and untested. If this is accurate, Russia has definitely violated the 1987 INF Treaty, but the U.S. may have come so close that the difference is negligible. The congressional 2018 defense budget guidance to the Pentagon to examine the cost of converting missiles such as the SM-3 interceptor to ground attack could bring us the last few steps to outright violation.

At the very least, the Russian Kalibr deployments and the U.S. deployment of MK41VLS launchers demonstrate how new threat perceptions and new technological capabilities are eroding the goals of the treaty.

US Complaints

The 2014, 2015, 2016 and 2017 Department of State reports entitled “Adherence to and Compliance with Arms Control, Nonproliferation and Disarmament Agreements and Commitments” all stated that the United States has determined that “the Russian Federation is in violation of its obligations under the INF Treaty not to possess, produce or flight-test a ground-launched cruise missile (GLCM) with a range capability of 500 kilometers to 5,500 kilometers, or to possess or produce launchers of such missiles.”

According to the April 2017 adherence report, "the United States requested to convene a session of the INF Treaty’s implementation body, the Special Verification Commission (SVC). Prior to 2016, the SVC had last met in October 2003 following the conclusion of the INF Treaty’s inspection regime in 2001." The report further states: "The United States has provided detailed information to the Russian Federation over the course of these bilateral and multilateral engagements, more than enough information for the Russian side to identify the missile in question and engage substantively on the issue of its obligations under the INF Treaty. This includes the following:

  • “Information pertaining to the missile and the launcher, including Russia’s internal designator for the mobile launcher chassis and the names of the companies involved in developing and producing the missile and launcher;
  • “Information on the violating GLCM’s test history, including coordinates of the tests and Russia’s attempts to obfuscate the nature of the program;
  • “The violating GLCM has a range capability between 500 and 5,500 km;
  • “The violating GLCM is distinct from the R-500/SSC-7 GLCM or the RS-26 ICBM."

The SVC meeting was held in October 2016, and the State Department presented its evidence to the Russian delegation again. The State Department, however, has so far declined to reveal publicly the specific missile in question or the evidence for its complaint. According to State Department officials who spoke with the author, the reason for this is to protect sensitive methods and sources for collecting the information.

In a Feb. 14, 2017, New York Times article, Michael Gordon wrote: "[T]he Russians now have two battalions of the prohibited cruise missile. One is still located at Russia’s missile test site at Kapustin Yar in the country’s southeast. The other was shifted in December from that test site to an operational base elsewhere in the country... Each missile battalion is believed to have four mobile launchers and a larger supply of missiles." Kapustin Yar is the birthplace of Soviet rocket development for the military and space programs.

According to Global Security, the defense and security news website, the missile in question is the SSC-X-8 (Russian nomenclature 9M729)—a land version of the long-range Kalibr ship-launched cruise missiles that have been used during Russia's operations in Syria. If true, this would mean that the range of the missile has been demonstrated to be greater than 500 km. (See also a Dec. 5, 2017, entry by Pavel Podvig on his Russian Forces blog that states U.S. National Security Council member and presidential advisor Christopher Ford identified the 9M729 missile as the INF violation.)

In a speech and question-answer session in Sochi in October 2017, Russian President Putin said of the INF Treaty: “[R]ecently we have been hearing many accusations about Russia violating this treaty by cooking up something. Maybe we would be tempted to do just that if we had no airborne and sea-based missiles. Now we have them. The U.S. had such missiles, and we did not,” which made the INF effectively a “unilateral disarmament treaty for the Soviet side.” Now that Russia has sea- and air-launched missiles, including the Kalibr, Putin argued, Moscow feels it’s simply leveled the playing field. “If someone does not like it and wishes to withdraw from the treaty, for example, our American partners, our response would be immediate,” he added. “I would like to repeat this warning: immediate and reciprocal. However, we have complied and we will [continue to] comply with our old treaties, as long as our partners comply as well."

It seems certain, based on a number of credible reports, that U.S. officials have provided the appropriate Russian officials with evidence of the treaty violation, but Russia refuses to acknowledge the breach.

Russian Complaints

Background: Russian complaints about U.S. adherence to the INF Treaty allege that the U.S. has developed and deployed systems that circumvent the treaty and give the U.S. an advantage for striking in the intermediate- and shorter-range battle space (between 500 and 5,500 km). For example, the U.S. has developed unmanned aerial vehicles that can deliver ordnance at ranges between 500 and 5,500 km, a feat previously accomplished only by cruise and ballistic missiles or manned aircraft. Russia is now attempting to do the same. Russian analysts also argue that use of the MK41VLS launcher in the Aegis Ashore missile defense system—a launcher whose ship-borne version is designed to fire both Tomahawk cruise missiles and SM-3 interceptors—gives the U.S. the ability to launch cruise missiles from land. Finally, although the production of intermediate and shorter-range ground-launched missiles is prohibited by the INF Treaty, both parties can legally continue to produce booster stages for such missiles under exceptions in the agreement. Russia has raised concerns over the years that the U.S. has taken advantage of these exceptions to develop components of a ballistic missile threat under the guise of conducting ballistic missile defense tests. While Russia’s complaints may emanate from a desire to curb American technology development or to distract the U.S. from Russia's own activities, it is nevertheless important to review carefully the complaints and ensure that U.S. compliance with the treaty is above reproach. 

Bottom Line Up Front: The Russian complaint about U.S. drones is refutable, but the case demonstrates the impact of new technologies on the efficacy of the treaty. The complaint about booster stages may warrant some U.S. action. The complaint about the MK41VLS launcher warrants U.S. action. Following is a short discussion of these points. 

Cruise Missiles and Drones

Russian Complaint: “[T]the United States has produced unmanned combat air vehicles, which fall under the INF category of land-based cruise missiles, for years. When we ask how this complies with the INF Treaty and accompanying documents, our American partners pretend not to understand our questions and resort to deliberations that are not directly connected with the INF Treaty terms and definitions” (comment by the Information and Press Department on U.S. allegations of the violation of the Intermediate-Range Nuclear Forces Treaty by Russia. MFA, Russian Federation, 2350-02-12-2015).

The Russian contention that U.S. drones that can fly in excess of 500 km and deliver ordnance on targets violate the INF Treaty ban on cruise missiles is not supported by a direct reading of the treaty’s text and it is undermined by logic. The Russian position is that U.S. drones are cruise missiles because they fall inside the definition of cruise missiles in Treaty Article II, paragraph 2: “an unmanned, self-propelled vehicle that sustains flight through the use of aerodynamic lift over most of its flight path.”

The Russian contention is based on faulty logic. Article II states that a cruise missile fits within the broader definition of “unmanned, self-propelled vehicle that sustains flight through the use of aerodynamic lift over most of its flight path,” which is true. Russian officials point out that drone aircraft also fit within the definition of “unmanned, self-propelled vehicle that sustains flight through the use of aerodynamic lift over most of its flight path,” which is also true. However, because drone aircraft and cruise missiles both fit within this broad category, it does not necessarily follow that aircraft/drones are equivalent to missiles.

In logic, if A (cruise missile) is a subset of C (unmanned self-propelled vehicles) and B (drone) is also a subset of C, it does not necessarily follow that A and B are equal. That proposition must be examined on its own merits. A and B are equal when A and B have the same properties and are interchangeable. A cruise missile and a drone share some properties but differ in others and are not always interchangeable. A missile, for example, is designed for a one-way trip to its destination. A drone is designed to return for reuse.

The entire treaty text makes clear that the prohibited weapon delivery vehicles are “missiles:” ground-launched cruise missiles and ground-launched ballistic missiles. To underscore that point, the two countries exchanged notes on May 12, 1988, in which they agreed that the Parties share a common understanding that the term ‘weapon-delivery vehicle’ in the Treaty means any ground-launched ballistic or cruise missile in the 500 kilometer to 5500 kilometer range that has been flight-tested or deployed to carry or be used as a weapon.” The operative noun throughout the treaty is “missile.”

Even though the Russian interpretation of drones as cruise missiles can be rebutted, the fact is that some drones have the capability today of doing what only cruise missiles could do at the time of the INF Treaty—i.e., unmanned delivery of weapons to the range of 500-5,500 km. These weapons, being pursued by both the U.S. and Russia, illustrate how the purpose of the INF Treaty is being eroded by new and unanticipated technologies. 

Booster Stages for Test Targets

Russian Complaint: “We also have questions about the use of target missiles during U.S. BMD tests with characteristics that are similar to those of intermediate- and shorter-range missiles. The scale of the production of the target missiles and the nature of their testing do not correspond to the declared goals. The United States could be using the alleged BMD tests to streamline the production and combat use of intermediate- and shorter-range ballistic missiles that are prohibited by the INF Treaty” (comment by the Information and Press Department on U.S. allegations of the violation of the Intermediate-Range Nuclear Forces Treaty by Russia, MFA, Russian Federation, 2350-02-12-2015).

In INF Treaty Article I, it is agreed that “each Party shall eliminate its intermediate-range and shorter-range missiles, not have such systems thereafter and carry out the other obligations set forth in this Treaty.” (In all cases, the treaty applies only to ground-launched systems.)

According to Treaty Article II, a ground-launched cruise missile (GLCM) or ground-launched ballistic missile (GLBM) must be a “missile that is a weapon-delivery vehicle.” 

INF Treaty Article VI states that after eliminating existing types of missiles, launchers and support equipment, neither party shall again “produce, flight-test or launch any intermediate-range [or shorter-range] missiles or produce any stages of such missiles or any launchers of such missiles.” 

The treaty allows for three exceptions to this prohibition: 1) The first exception (Article VI, paragraph 2) allows GLBMs that are not prohibited by the treaty (e.g., missiles with a range other than 500 to 5,500 km or those that are not “weapon-delivery vehicles”) to use a stage that is outwardly similar to, but not interchangeable with, a stage from a prohibited GLBM having more than one stage, providing that the party country does not produce any other stage that is outwardly similar to, but not interchangeable with, any other stage of an existing type of intermediate-range GLBM. 2) A second exception (Article VII, Paragraph 3) is for a GLBM that “is of a type developed and tested solely to intercept and counter objects not located on the surface of the earth” such as an SM-3. 3) The third exception (Article VII, paragraph 12) allows each party “to produce and use for booster systems, which might otherwise be considered to be intermediate-range or shorter-range [ground-launched] missiles, only existing types of booster stages for such booster systems” (largely to allow for target missiles used in ballistic missile defense tests). The U.S., however, has been developing and using new boosters and missiles as targets. The Missile Defense Agency’s new Flexible Target Family (FTF) may fall outside these three exceptions.

In 2003, the Missile Defense Agency (MDA) began seeking ways to improve target missile reliability and to reduce costs. There were several problems with existing target missiles including target availability and aging components leading to missile failures. “For example, motors used in some targets are now over 40 years old.” Initially, MDA contracted with Lockheed Martin to develop a new family of target missiles—the above-mentioned FTF (GAO Report, GAO-08-11130, “DEFENSE ACQUISITIONS, Sound Business Case Needed to Implement Missile Defense Agency's Targets Program” Sept. 2008).

The MDA’s 2007 Environmental Assessment for the new FTF stated that “[t]he FTF would streamline MDA’s target acquisition process by using a collection of common boosters, front sections and components to assemble a variety of different target configurations.” According to the above-cited GAO Report, the MDA’s goals in pursuing the FTF “included commonality of components across the family of short-, medium- and long-range targets, the purchase of inventory, reduced cycle time in the building of individual targets, increased complexity, cost savings and ground, air and sea launch capabilities.” A May 13, 2013, press release by Lockheed Martin stated that “[u]nder the Targets and Countermeasures Prime Contract, Lockheed Martin is developing and producing a total of 17 missile targets of various types and ranges.”

Developing and using the new FTF boosters in intermediate- and shorter-range missiles is permissible only if they fall under one of the three exceptions in the treaty. The second exception for missile defense interceptors is not applicable for the target systems.

The new FTF boosters would seem not to fall under the third exception in Article VII, paragraph 12, since they are not “existing types of booster stages.”

Finally, the argument that the FTF boosters are allowed under the first exception (Article VI, paragraph 2) because the target systems are not “weapon delivery vehicles” is debatable, since each target, according to Lockheed Martin, is "as complex as the threat it emulates and includes a launch vehicle, a payload, launch support equipment, instrumentation and a flight control station."  

Even if both sides agree that the target systems in question are not “weapon-delivery systems,” the boosters could still fall outside the first exception if they are part of a two-stage booster system. The Lockheed Martin LV-2 intermediate-range ballistic missile target for Aegis BMD is a two-stage target missile in the Flexible Target Family and has been in use since 2011.

 The decision to create the new FTF missiles to provide improved short-, intermediate- and long-range targets may have resulted in the development and testing of new booster stages prohibited by the INF Treaty and this deserves review by U.S. officials.

Cruise Missile Launchers

Russian Complaint: “The MK-41 VLS is installed on surface ships for launching Standard-3 interceptors and Tomahawk intermediate-range cruise missiles. A Pentagon representative said at the hearings that the land-based MK-41 is not suited or designed to launch cruise missiles. We don’t consider this question to be settled, because only military and technical experts can determine if the above statement is true, while our American partners refuse to hold a practical discussion on this. Therefore, we consider it reasonable to view the ground-based MK-41 VLS as a cruise missile launcher, and its deployment on dry land as a direct violation of the INF Treaty”(comment by the Information and Press Department on U.S. allegations of the violation of the Intermediate-Range Nuclear Forces Treaty by Russia. MFA, Russian Federation, 2350-02-12-2015).

The question of the MK41 Vertical Launch System (VLS), which is deployed on Aegis ships and is now being used as the Aegis Ashore missile-defense launcher, stems from the fact that it was originally designed and built to fire a variety of missiles including both SM-3 missile interceptors and Tomahawk cruise missiles. According to the builder/designer, Lockheed Martin, the MK41VLS “can simultaneously accommodate the weapon control system and the missiles of every warfighting mission area—anti-aircraft, anti-surface, antisubmarine and land attack. … The basic module is available in three sizes: Strike, Tactical and Self-Defense. The Strike module is approximately 25 feet (7.6 meters) long and capable of launching the largest missiles such as those that support sea-based midcourse ballistic missile defense [SM-3 interceptors] and long-range strike [Tomahawk cruise missiles].”

The INF Treaty divides prohibited items into three basic categories: missiles, launchers and associated support equipment. Articles IV and V of the treaty require both parties to eliminate all existing ground-launched intermediate- and shorter-range ballistic (GLBM) and cruise missiles (GLCM), their launchers and all associated support equipment. The GLCM launcher that was eliminated under these articles was the launcher for the BGM-109G (Gryphon).

Article VI states that after eliminating existing types of missiles, launchers and support equipment, neither party shall again “produce, flight-test or launch any shorter-range missiles or produce any stages of such missiles or any launchers of such missiles.” In this sense, the parties may not produce any new launcher that can be used to launch from the ground a ballistic missile or cruise missile with the prohibited range of 500-5,500 km. The launcher used for Aegis Ashore (MK41VLS) is a new launcher that can fire, from the ground, a Tomahawk cruise missile that has a range between 500 and 5500 km.

The U.S. argument that the ground-based MK41VLS launcher is not a violation because of the absence of supporting software, fire control hardware, additional equipment and infrastructure to enable the launcher to fire a cruise missile would not seem to have bearing on the admissibility of the launcher itself. According to Article II, “the term ‘GLCM launcher’ means a fixed launcher or a mobile land-based transporter-erector-launcher mechanism for launching a GLCM.” The term “launcher” describes a part of the system, separate from the missile and the supporting equipment (like control panels, cabling, etc.)—each of which must be eliminated or made nonoperational in their own right. For example, a launcher is independent and separate from the missile canister, transporter/erector or other equipment that might be associated with the launcher. According to paragraph 10 in the Memorandum of Understanding (MOU) for the treaty, “the term ‘support equipment’ means unique vehicles and mobile or transportable equipment that support a deployed intermediate-range or shorter-range missile or a launcher of such a missile.” Each of these components—missile, launcher and support equipment—is prohibited. In this sense, a launcher capable of firing a prohibited missile, even if it is not connected to the associated equipment items that enable it to fire the missile, cannot be deployed. It would seem that the ground-based MK41VLS launcher itself must be made incapable of launching a cruise missile, regardless of the availability or role of additional supporting equipment or the missile itself.

The treaty does not speak directly to the case of the Aegis Ashore system because negotiators did not envision that a ship-based launcher, which is capable of launching both offensive cruise missiles and defensive missile interceptors, would be moved to a ground site and selectively used to launch missile interceptors. However, in Section II of the INF Treaty’s MOU, Item 4 specifies that the goal of eliminating GLCM and GLBM system components is “to preclude the possibility of restoration of such items for purposes inconsistent with the provisions of the Treaty.”

To stay within the spirit and letter of the treaty, while continuing to use the MK41LVS launcher in land-based ballistic missile defense, the U.S. can look at precedents from similar problems covered in the treaty. An analogous situation is the use of ground-based launchers to test missiles intended for naval use (Article VII, Item 11). In that case, the treaty requires that the launcher be “distinguishable from GLCM and GLBM launchers.” While it is true that the INF Treaty does not state that “distinguishing” characteristics must be “observable and permanent,” most arms control verification measures depend on some form of observability and permanence. For example, the INF Treaty itself requires cutting, crushing or other destruction to eliminate system components—steps that are observable and final. One remedy, therefore, could be to make observable and permanent changes to MK41VLS launchers used in the ground-based ballistic missile system that would permit firing of SM-3 missiles but distinguish them from MK41VLS launchers that can fire a cruise missile.


  1. Russian name: RSD-10 Pioneer, GRAU number 15Zh45; a GRAU number is an index assigned by the Main Missile and Artillery Directorate of Russia’s Defense Ministry (GRAU).
  2. The Soviet Union's perception of being behind in the 1970s was exaggerated as it had reached relative parity in strategic nuclear weapons and retained a sizable conventional advantage in Europe, where a conflict with the U.S. would most likely start. Nevertheless, the USSR acted on that perception, just as Russia today is acting by developing and testing ground-launched medium range missiles.
  3. In 1979, after the beginning of Russia's SS-20 deployments, NATO and the U.S. adopted the "dual track" approach to Russian deployments, which directed arms talks with Russia at the same time it authorized the development and deployment of American Pershing and cruise missiles to counter the Russian buildup.
  4. NATO-based U.S. envoy Robert Bell commented on the opening of a U.S. BMD site in Deveselu, Romania: “We now have the capability to protect NATO in Europe. … The Iranians are increasing their capabilities and we have to be ahead of that. The system is not aimed against Russia.” Reuters, May 11, 2016.
  5. "Conventional Warheads for Long range Ballistic Missiles: Background and Issues for Congress," Congressional Research Service, Jan. 26, 2009, p. 4: "In May 2003, the Air Force issued a formal Mission Need Statement for the Prompt Global Strike (PGS) Mission. This document was written by Air Force Space command, coordinated with officials in the Joint Staff and the Office of the Secretary of Defense, and validated by the Joint Requirements Oversight Council (JROC). This statement indicated that the United States should be able to strike globally and rapidly with joint conventional forces against high-payoff targets. The United States should be able to plan and execute these attacks in a matter of minutes or hours, as opposed to the days or weeks needed for planning and execution with existing forces, and it should be able to execute these attacks even when it had no permanent military presence in the region where the conflict would occur." (Attributed to: Jumper, John, General, U.S. Air Force. Final Mission Need Statement. “Prompt Global Strike,” May 2, 2003.) Congress has not fully funded this initiative over the years and has expressed concern that Russia might misunderstand the launch of a conventional missile and think it was under nuclear attack.
  6. 2018 NDAA Bill, Title XII, Subtitle E, Section 1243, Nov. 16, 2017, (sent to president) authorizes $58 million for: (1) ESTABLISHMENT OF A PROGRAM OF RECORD.—The Secretary of Defense shall establish a program of record to develop a conventional road-mobile ground-launched cruise missile system with a range of between 500 to 5,500 km, including research and development activities with respect to such cruise missile system.
  7. Article I of the 1987 INF Treaty states: "In accordance with the provisions of this Treaty …, each Party shall eliminate its intermediate-range and shorter-range missiles, not have such systems thereafter, and carry out the other obligations set forth in this Treaty." Conducting "research and development" is a vague phrase that could be interpreted to permit the construction of a treaty-banned missile as long as it were not test fired. Test firing, although useful, is not necessarily required in today's computer simulation environment. Further, the development and production of launchers and control systems could all be done without "test firing." Conducting research and development may be technically permissible under the treaty, but it runs counter to the spirit of the agreement and puts compliance in doubt at a time when treaty inspections are no longer obligatory.
  8. Speech to students and faculty of Middlebury Institute, as well as associates of James Martin Center for Nonproliferation Studies, Dec. 2, 2017.
  9. The final version of the 2018 NDAA bill sent to the president on Nov. 16, 2017, requires the secretary of defense to report "on the cost and schedule for, and feasibility of, modifying United States missile systems in existence or planned as of such date of enactment for ground launch with a range of between 500 and 5,500 km as compared with the cost and schedule for, and feasibility of, developing a new ground-launched missile using new technology with the same range." The Senate version of the bill dated Sept. 18, 2017, Section 1635, actually listed some of the systems being considered for modification, "including the Tomahawk Cruise Missile, the Standard Missile-3, the Standard Missile-6, the Long-Range Stand-Off Cruise Missile, and the Army Tactical Missile System, as compared with the cost and schedule for, and feasibility of, developing a new ground-launched missile using new technology with the same range." Russian security strategists have alleged the U.S. BMD systems (SM3 etc.) will be used as offensive threats.
  10. According to the CIA Factbook, as updated on Nov. 14, 2017, median age of Americans is 38.1 years.
  11. Mandatory retirement for military servicemen and women is 30 years, unless an exception is granted as in the case of promotion to general officer.
  12. The author was witness to the request in 1990 during service with the U.S. Military Liaison Mission in Berlin.
  13. U.S. Department of State, INF Treaty Text, Narrative.
  14. In Russian, the agreement is referred to as the “RSMD Treaty.”
  15. For example, in the 1987 INF Treaty both sides agreed to locate delivery systems at announced locations; an analogous arrangement could be made for nuclear warheads. E.g., INF Treaty, Article VIII, Paragraph 5: "All deployment areas, missile operating bases and missile support facilities are specified in the Memorandum of Understanding or in subsequent updates of data pursuant to paragraphs 3, 5(a) or 5(b) of Article IX of this Treaty. Neither Party shall increase the number of, or change the location or boundaries of, deployment areas, missile operating bases or missile support facilities, except for elimination facilities, from those set forth in the Memorandum of Understanding."

Kevin Ryan

Brigadier General Kevin Ryan (U.S. Army retired) is an associate fellow at Harvard Kennedy School’s Belfer Center for Science and International Affairs and former chief of staff, Army Space and Missile Defense Command.

The author takes full responsibility for the article, but wishes to thank Matthew Bunn, Martin Malin, Rolf Mowatt-Larssen, Simon Saradzhyan, Natasha Yefimova-Trilling and others at the Belfer Center for their advice in preparing this material.

Photo credit: George Chernilevsky

The opinions expressed in this commentary are solely those of the author.