Some in Congress are agitating for action regarding possible Russian violations of the 1987 Intermediate-Range Nuclear Forces (INF) Treaty. That treaty prohibits the United States and Russia from having land-based ballistic and cruise missiles with ranges between 500 and 5500 kilometers (300-3400 miles). One noncompliance charge concerns the RS-26 ballistic missile, but that missile does not violate the INF Treaty’s terms. The other charge, regarding a cruise missile, appears to pose a more serious question for the treaty.

Maintaining the INF Treaty remains in the interest of the United States. American allies value the agreement, and the U.S. military has no stated plans for intermediate-range missiles of its own. The U.S. government should press Russia to clarify the status of the cruise missile and, if the missile does indeed violate the treaty, to end the program. In addition to raising this issue with Moscow, Washington should brief Russia’s neighbors, both in Europe and Asia, on what it knows about the Russian cruise missile. Those countries will be in range of the missile; the United States will not.

President Ronald Reagan and General Secretary Mikhail Gorbachev signed the INF Treaty in December 1987. It resulted in the elimination of 846 American and 1846 Soviet INF missiles, their launchers and associated equipment.

Beginning two years ago, charges have circulated regarding possible Russian violations of the treaty. Assertions that the RS-26 ballistic missile represents a violation reflect an incorrect reading of the INF Treaty and New Strategic Arms Reduction Treaty (New START).

Those claims focus on the fact that Russia has tested the RS-26 at ranges less than 5500 kilometers. But the RS-26 has also been tested at ranges greater than 5500 kilometers. According to the New START Treaty, a land-based ballistic missile “with a range in excess of 5500 kilometers” is an intercontinental ballistic missile (ICBM)—a permitted missile captured by New START. The INF Treaty bans missiles with ranges “in excess of 500 kilometers” but not “in excess of 5500 kilometers.” By these definitions, the RS-26 counts as a permitted ICBM, not a prohibited intermediate-range ballistic missile.

Some have argued that the Russians tested the RS-26 to an ICBM range to ensure that it would be “legal,” while actually intending to aim it at targets at intermediate ranges. While that may be true, it would not constitute a treaty violation.

The use of ICBMs at less than intercontinental ranges has always been possible. The INF Treaty required the Soviet Union to destroy hundreds of modern SS-20 intermediate-range ballistic missiles. When U.S. officials assessed how the Soviets, without the SS-20, would strike time-urgent targets, they concluded that the Soviets would dedicate some ICBMs to the mission, flying them at less than intercontinental range. The Reagan administration fully accepted that possibility.

If Russia builds RS-26 ballistic missiles for use against targets at intermediate-range, but the arms-control regime treats and counts them as ICBMs, that creates an interesting situation. Unless based in Russia’s far-eastern regions, those missiles could not reach U.S. territory. Yet each RS-26 missile and each RS-26 warhead would count under New START’s limits—possibly displacing ICBM warheads that could target all of the United States. (The Russians are well below New START’s limit on deployed missiles and bombers, so RS-26 missiles would not displace ICBMs.)

The alleged Russian cruise-missile violation is a different story. Unfortunately, open sources tell us little, except that Russia may be testing an intermediate-range cruise missile—often referred to as the R-500—and that U.S. officials briefed NATO allies about their concern over this in January. One member of Congress has said that the Russians claim the missile is a sea-launched cruise missile—significant, because sea-launched cruise missiles are not limited by any treaty—but the administration has not confirmed this.

The State Department is preparing its annual compliance report for Congress, which presumably will address the cruise-missile question. While reportedly in final preparation, the State Department has missed the April 15 due date, not unusual for such reports. (The George W. Bush administration’s State Department did not submit any reports from 2006-2008.)

The report could state that the R-500 cruise missile is a violation of the INF Treaty, or it could say that the question is still under review. Reaching judgments on compliance can be a difficult process.

If the U.S. government concludes that the cruise missile violates the INF Treaty, which steps should it take to address its concerns? Some would suggest withdrawal from the treaty, but immediate withdrawal would not be a smart move.

First, unless U.S. officials can offer convincing evidence of a Russian treaty violation—no easy task, especially considering “sources and methods” issues will argue to keep information classified—Washington could be seen as responsible for ending the treaty. Senior Russian officials openly pondered withdrawal from the treaty in 2007, but Moscow would certainly prefer that Washington initiate withdrawal and take the heat.

Second, the U.S. military has no plans for land-based intermediate-range missiles. Developing such missiles would take time and would burden an already stretched Pentagon budget that is struggling to fund modernization of U.S. strategic nuclear forces.

Third, even if the United States were to build intermediate-range missiles, where would it deploy them? Those missiles would have a serious mission only if forward deployed in Europe, Japan or South Korea. How likely is that?

U.S. deployment of its intermediate-range nuclear missiles—Pershing II ballistic missiles and ground-launched cruise missiles—to Europe in the 1980s proved the key factor in motivating Moscow to agree to ban intermediate-range missiles. But deployment in Europe was a close thing. NATO officials worried that some of the five basing countries would, in the end, be unable to accept the U.S. missiles due to the depth of political and public opposition. U.S. INF negotiator Paul Nitze took his famous “walk in the woods” with his Soviet counterpart and suggested an agreement that differed from the official U.S. negotiating position, because he feared that NATO would not be able to deploy Pershing IIs or ground-launched cruise missiles—and that the resulting fall-out would tear the Alliance apart.

Few who went through the INF deployment process would relish the chance to do so again. It is not clear that many, if any, NATO members would be eager to host such missiles. Those most likely to offer to do so are in Central Europe. Deployment there, however, would put the missiles in places where they would be exposed to a preemptive strike and be hugely provocative to Moscow (think 1962 Cuban missile crisis).

There would likely be no takers for U.S. INF missiles in Asia, either. Japan would worry about the effect of such deployments on its effort to improve its relationship with Russia and, in any case, would not accept nuclear-armed missiles. South Korea is building its own missiles to hold targets in North Korea at risk and would fear that deployment of U.S. missiles might disrupt its warming relations with China.

So, it may make sense for the United States to abide by the INF Treaty even if questions linger about Russian compliance or there is a conclusion that a violation has occurred. Previous administrations observed arms-control agreements even in the face of outright treaty violations by Moscow.

Take the Reagan administration. The 1972 Anti-Ballistic Missile (ABM) Treaty limited the United States and Soviet Union each to one ABM interceptor deployment area. In order to ensure that large phased array radars (LPARs) located outside those deployment areas could be used for early warning but not battle management (i.e., guiding interceptors to their targets), the treaty required that such LPARs be located on the periphery of a country’s territory and oriented outward.

In 1983, the U.S. intelligence community detected the construction of an LPAR at Krasnoyarsk in central Siberia. The problem: the radar was more than 800 kilometers (500 miles) from the Russian-Mongolian border and, instead of being oriented outward—i.e., toward the south—it faced to the east, over a broad expanse of Russian territory.

The Reagan administration judged that the radar constituted a violation of the ABM Treaty. U.S. officials raised the radar at the fall 1983 session of the Standing Consultative Commission, the body established by the ABM Treaty to address, among other issues, questions about compliance with the treaty.

The Soviets asserted that the Krasnoyarsk LPAR would be used for space-track purposes, an implausible claim given that few space orbits would pass through the radar’s field of view. However, the LPAR did have an excellent view of the attack corridor for U.S. submarine-launched ballistic missiles flying out of the northern Pacific Ocean to targets in the central Soviet Union. That plugged a gap in the Soviets’ early warning radar coverage; to have the same early warning coverage in a way consistent with the ABM Treaty, the Soviets would have had to build two LPARs in the Soviet Far East.

A January 1984 White House report to Congress said the Krasnoyarsk LPAR “constitutes a violation of legal obligations under the Anti-Ballistic Missile Treaty of 1972 in that in its associated siting, orientation and capability, it is prohibited by this Treaty.” U.S. officials continued to press the Soviets on the radar.