While MIRV development continued, ABM development was brought to a virtual standstill. The ABM Treaty permitted each side to deploy 100 missiles to defend a chosen land-based missile-silo basing site and another 100 to defend the national capital city. America deployed its Safeguard ABM in 1974 at the missile base in Grand Forks, North Dakota. Safeguard consisted of a two-layer defense: the Spartan missile designed to intercept ballistic missiles above the atmosphere, and the Sprint missile designed to intercept at low altitude missiles that Spartan missed. The system was never deployed around Washington, D.C., due to very understandable popular resistance to deploying five-megaton warheads close to heavily populated areas. The system at Grand Forks was dismantled in 1976. A 1974 protocol (add-on) to the ABM Treaty limited Russia to 100 ballistic missile interceptors.[57]
The systems ultimately deployed by the United States were “dumbed down”—deliberately made less capable of intercepting incoming warheads—in order to conform to arms-control agreements as interpreted by arms controllers. Specifically, radar capabilities and access to satellite tracking data were restricted. Thus when a Scud missile (a short-range, primitive Soviet ballistic missile system sold to several Mideast countries) destroyed a barracks and killed American servicemen in Dhahran, Saudi Arabia, near the end of the Gulf War, the dumbed-down Patriot-3 system failed. It is reasonable to believe, though not definitively provable as it is the road not taken, that unfettered development of missile defense technology would have produced a system able to destroy the Scuds launched during the Gulf War (most landed in Israel). Thus arms agreements already have plausibly prevented deployment of lifesaving defensive systems.
Much of the opposition to missile defense was based upon the sheer infeasibility of defeating a massive missile salvo of the kind the Soviet Union could have launched, using the kinds of systems deployable within arms-control constraints. The uncertainties were similar to those faced by prospective attackers using a large fleet of missiles. Put simply, systems were tested in small numbers, with many tests solo. There is no way for technologists to gauge from such tests how the same systems will perform when used on a large scale. Test trajectories and war trajectories differ, with aim “bias” introduced by asymmetries in the Earth’s magnetic fields. System performance, in a nutshell, may not scale in uniform, linear fashion. Thus offensive system behavior in situations other than those specifically tested cannot confidently be predicted by attacker or defender.
Systems currently deployed intercept missiles either in their final (terminal) phase of flight or in midcourse. Terminal-phase intercept involves separating heavier warheads from lighter decoys in the closing seconds, made possible when warheads encounter friction in the atmosphere, which then separates the two based upon weight and density differentials. But with time so short, taking out a large salvo—even if defense radars were not destroyed, a highly shaky assumption—is a complex task. Midcourse intercept targets ballistic missiles coasting in space on unalterable trajectories (like artillery shells), but where the zero gravity of space makes separating warheads and decoys extremely difficult.
The result is a set of complex trade-offs, well illustrated by Paul Nitze in his memoirs. The early U.S. systems relied on nuclear warheads to destroy warheads with near misses. The altitude at which decoys begin to slow down sufficiently to be separated from actual warheads is about 250,000 feet, just under 50 miles up. Under 100,000 feet—19 miles up—marks a line below which detonating nuclear devices is out of the question when defending cities. This offers some 30 miles in which to engage decoys; below 19 miles, nonnuclear or kinetic-impact missile defense warheads must be used. Silo defense is less demanding, as incoming warheads can be engaged well below 100,000 feet, where lighter decoys are out of the way, and thus genuine warheads will be easier to identify.
Ultimately perhaps more promising, but strongly opposed by the Russians, are boost-phase intercept systems that target missiles shortly after launch. The missile is traveling far more slowly than in space; decoys cannot be released and thus intercept could well work, even on a large scale. But such systems, which employ lasers, have had to compete for funding with other defensive ideas. Because such intercepts would likely take place over the attacker’s territory, potential attackers, including Russia, vigorously oppose their deployment.
In the 1970s the Russians conducted extensive laser beam defense experimentation at their Sary Shagan site in central Asia. Their technology was simply not up to the exacting task then, nor does it appear to be even today. American efforts have shown promise, but to date no system has proved itself against ICBMs. President Reagan was much taken by H-bomb father Edward Teller’s X-ray laser concept: when an atomic device detonated, a laser based in space would emit intense X-rays that could destroy large numbers of attacking warheads in flight. Teller’s concept was highly original, but eventually was abandoned, partly due to arms-control considerations about space weaponry and partly due to technical reservations. All large laser systems raise serious power problems. As noted in chapter 13 the Airborne Laser program was cancelled for this reason. (It used lasers mounted on a 747 aircraft to target missiles.).
The Russians even objected to a midcourse intercept system promised to the Czech Republic and Poland in 2006 by President Bush, claiming that it would also be capable of tracking missiles in boost phase and possibly intercepting them. This gave President Obama a rationale in 2009 to justify unilaterally abrogating the 2006 deal. However, he negotiated not with our Eastern European partners but with Moscow, notifying the affected allied leaders a mere 25 minutes before announcing the swap of a land-based missile defense system for a sea-based one. The Obama administration asserted that the new system is better than the one promised our allies in 2006, but if this were true, why didn’t the United States approach these allies and tell them what a great deal it is? Thus did Cold War arms-control doctrine govern President Obama’s signature arms treaty, and trump concerns of two of our closest allies.
David Hoffman’s The Dead Hand offers a prime example of how hard violations issues are to definitively resolve. The Russians built a massive radar tracking facility at Krasnoyarsk, 1,869 miles inside the Soviet Union, with radar oriented inward. The ABM Treaty limited each side to a single radar protecting the capital, plus perimeter radars at the coastline. This was intended to prevent radars being used for “battle management”: directing large salvos of missiles to thwart a large-scale attack. At the perimeter, radars could take out individual missiles or small salvos but not represent a comprehensive shield. The U.S. maintained that the Krasnoyarsk facility was illegal because it was centrally located and also designed for battle management. On location the U.S. was clearly right. As to the system’s purpose, Hoffman contends it was to plug a hole in Russian defenses, not manage a large-scale defense, and thus a minor violation. In 1989 the Soviets openly admitted that the Krasnoyarsk facility indeed was a violation of the ABM Treaty.
That it took a confession by the Russians to establish a violation showed the infirmity of Cold War arms treaty enforcement. Russia could violate the ABM Treaty with impunity, without fear of being condemned for it. Absent a supervening legal authority capable of rendering judgment, let alone enforcing same, protesting Soviet violations amounted to shouting into the wind.
Thus has missile defense, for 40 years, been held hostage to arms control limits—even after the U.S. exited the ABM Treaty a decade ago.