it in sight using the attitude control system. In the next phase, the interceptor would perform a series of more radical maneuvers in order to characterize the performance of the controls and the tracking system in a more realistic scenario. Finally, the system would perform another series of smaller maneuvers intended to be more accurate movements. This test was largely a failure; the system failed to pick up the target, and all of the subsequent movements were found to be much less accurate than required, to a large degree due to the failure of the gyroscopes. Some useful data characterizing the IR background was performed, but the UV sensor only recorded its own background noise. The final test was carried out on 22 October 1992, using a much more developed prototype built by Livermore that had been miniaturized and was more indicative of a production model. This test would begin like the others, with both the kill vehicle and the target being launched from a single rocket at Wallops Island. Once the two vehicles separated, the kill vehicle was to begin tracking the target, and then use its propulsion system to bring it to within of the target vehicle. Seventeen seconds after liftoff the ground crew could see pieces falling off the booster, and it was destroyed by the range safety officer at 55 seconds. The problem was later traced to a failure in one of the rocket nozzles in the Aries I first stage. Countermeasures Earlier anti-ballistic missile (ABM) systems like Nike Zeus had the problem that they cost more than the ICBMs they were designed to shoot down; the United States would have to purchase $20 worth of interceptors for every $1 the Soviets spent on new ICBMs. In such a situation, the Soviets could defeat any possible ABM deployment simply by building more missiles. This was a major argument against ABM systems in the 1960s and 70s. This led Paul Nitze to propose what became known as the Nitze criteria; to be successful, the marginal cost of adding to the defense had to be less than the cost of adding to the offense. If this is not true, then the simplest response to any new defense system is simply to build more offensive missiles. But if the defense is cheaper, this will not work, and the enemy will have to explore other solutions to address the imbalance.