To the Editor:
John Pike's article "Ballistic Missile Defense: Is the U.S. 'Rushing to Failure'?" (April 1998) mischaracterizes the ABM Treaty modifications signed by the United States and Russia last fall. (See ACT, September 1997.) He correctly points to the large hole these modifications open in the treaty, but overstates the extent to which the Clinton administration achieved its objective of changing the accord to accommodate its missile defense plans.
Although the administration declared these treaty modifications to be a successful conclusion to almost four years of difficult negotiations with Russia, a look at the agreements themselves reveals that the United States failed to get the deal it wanted—despite pushing Moscow very hard. It was precisely because of this failure that the United States announced that each country would individually determine the treaty compliance of its defense systems.
The administration spin on the agreements is, in part, intended for domestic consumption—in particular, to convince Senate Republicans that the ABM Treaty would not stand in the way of U.S. missile defense programs. But it may also be intended as a warning to Russia that, regardless of what the modifications actually permit, the United States intends to go forward with its missile defense programs. For this reason, it is especially important to understand what the modifications do and do not permit, and for the U.S. arms control community to hold the United States to the terms of the treaty.
The ABM Treaty limits strategic missile defenses, and to prevent circumvention it places two restrictions on other types of defenses (for example, defenses against aircraft and theater missiles). Such defenses may not be tested against strategic missiles and may not be given a capability to counter strategic missiles. But the treaty does not specify what a strategic missile is nor how to assess whether a defense has a capability to counter strategic missiles. The nominal goal of the U.S.-Russian talks was to draw a clear line between prohibited and permitted defenses. The United States was seeking to draw this line so that all its planned theater missile defenses would be legal.
The U.S. opening proposal was to simply drop the restriction on capability and retain the restriction on testing by defining a strategic missile as one with a range greater than 3,500 kilometers (and hence a reentry speed of greater than 5 kilometers per second). Thus, any system that was not tested against a target travelling faster than 5 kilometers per second would be legal, regardless of its inherent capability. The Russian counterproposal was to also limit the speed of the defense interceptor to 3 kilometers per second. This would permit the Theater High Altitude Area Defense (THAAD) system but not the Navy Theater Wide system. The United States wanted no limits on interceptor speed.
The agreement reached four years later demonstrates that very little progress was made. The so-called First Agreed Statement (dealing with lower-velocity systems) is essentially the Russian counter-proposal: it permits all defense systems with interceptors slower than 3 kilometers per second as long as they are not tested against targets travelling faster than 5 kilometers per second.
However, the Second Agreed Statement, which covers "high-speed" defenses with interceptors faster than 3 kilometers per second, has a very different character from the "low-speed" agreement and is really an agreement to keep talking. It does not specify which types of ground-, sea- or air-based systems are permitted or prohibited, although it stipulates that any permitted systems must adhere to the same 5-kilometer-per-second testing restriction. Moreover, it goes on to state that parties to the treaty will continue to hold consultations on high-speed defenses. There is no wording in the agreement to support the U.S. assertion that compliance decisions will be made by the owner country. The agreement does clearly prohibit all space-based interceptors, which are inherently capable of strategic defense.
Thus, Russia did not sign off on Navy Theater Wide. Equally important, Moscow has not signed off on space-based tracking systems—such as the low-altitude component of the Space-Based Infrared System (SBIRS-low)—that the United States is developing and planning to deploy in the next decade. Indeed, in a recent interview, Viktor Koltunov, the head of the Russian delegation to the ABM Treaty talks, notes that "…if such space-based systems, capable of providing target acquisition and counter-missile guidance, were developed it would be a significant breach of the agreements reached." ("Additional Limitations on Theater Missile Defense Systems will be Considered as New Systems Technologies are Developed," interview with Viktor Koltonov, Nuclear Control Digest, No. 7, Spring 1998, originally published in Yaderny Kontrol, No. 36, December 1997, PIR Center, Moscow.)
Satellite systems that could guide the interceptor to an incoming warhead would eliminate the need for the interceptor to be controlled by a ground-based radar, and thus permit very large defended areas (using high-speed interceptors) against strategic missiles. In the same way that space-based interceptors are inherently strategic capable, so are space-based tracking systems. The ABM Treaty addresses the issue of such satellite systems, which in the language of the treaty are components "based on other physical principles" that are "capable of substituting for ABM radars." Such components are subject to discussion and the treaty can be amended to permit or limit them, but the provisions of the original ABM Treaty stand until they are modified by agreement. It follows that such satellite systems are not permitted under the current treaty, even with the recent modifications.
Deep reductions in nuclear weapons will be much more difficult to achieve (if not impossible) without effective constraints on strategic-capable missile defenses. What will happen in the future will depend on many complicated factors—both international and domestic. It is true that Russia could agree to further weaken the treaty in the future, especially if it is pressured to do so in exchange for continued U.S. economic assistance. It is also true that the United States seems poised to go forward with its SBIRS-low and Navy Theater Wide programs by simply declaring them to be treaty compliant. This makes it all the more important that U.S. arms controllers not throw in the towel yet, but continue to insist that the United States abide by the actual modified treaty rather than its unilateral interpretation of it.
Senior Staff Scientist, Union of Concerned Scientists and Research Fellow, Security Studies Program, MIT