The Russians sought interceptor performance limits by restricting maximum velocity. The United States took the position that such limitations were unnecessary and unrealistic. Our systems, particularly taking into account TMD numbers and deployment configuration, would not have a realistic operational capability against strategic ballistic missiles. Furthermore,, a system that had not been tested against a strategic ballistic missile could not be counted on to carry out an ABM mission and therefore would not be procured for that-mission. We also argued that parameters such as interceptor velocity alone could not determine whether or not a system had ABM capability.
Many factors contribute to the capability to intercept a strategic ballistic missile.
To seek to take account of all of those factors would have threatened to create a new treaty regime. This the United States was not prepared to accept. In mid-1994, the United States responded to Russian proposals with a counterproposal of its own. While not accepting the validity of performance constraints, the United States stated it would be prepared to accept certain limits on interceptor capability, as long as those limitations would not inhibit the performance of the systems the United States was planning to develop. In fact, this counterproposal went a long way to resolving the differences between us and the other sides.