Intensive research has been undertaken to examine the modalities of a possible agreement without the need for access to the territory of the other party. Both the ABM Treaty and the interim agreement stipulate that compliance must be ensured by “national technical verification means”. In addition, the agreements contain provisions that are important measures to enhance the security of offences: both parties agree not to interfere in national technical control. In addition, both countries agree not to take deliberate cover-up measures to impede the review. In August 1972, the U.S. Senate approved the agreements by an overwhelming majority. Salt-I, as we have learned, served as the basis for all the discussions on weapons limitation that followed. Even after the Vladivostok agreements, the two nations were unable to resolve the other two outstanding issues of SALT I: the number of strategic bombers and the total number of warheads in each nation`s arsenal. The first was made more difficult by the Soviet Bomber Backfire, which American negotiators thought could reach the United States, but which the Soviets did not want to include in the SALT negotiations. Meanwhile, the Soviets tried unsuccessfully to limit the American use of cruise air missiles (ALCMs). The audit also divided the two nations, but they eventually agreed on the use of National Technical Means (NTM), including the collection of electronic signals known as telemetry and the use of photo recognition satellites.
On June 17, 1979, Carter and Brezhnev signed the SALT II Treaty in Vienna. Salt II limited the total number of nuclear forces from both countries to 2,250 delivery vehicles and imposed numerous additional restrictions on core strategic forces, including MIRVs. Finally, as negotiated, the SALT-II Treaty limited the number of strategic launchers (i.e. missiles that could be equipped with several independent re-entry vehicles [MIRV]) return vehicles, with the aim of repeling the moment when land-based ICBM systems on both sides would become vulnerable to attacks by these missiles. The number of MIRVed ICBMs, MIRVed SLBMs, heavy (i.e. long-range) bombers and the total number of strategic launchers were limited. The treaty set a total limit of about 2,400 of all these weapons systems for each side. The SALT II Treaty was signed in Vienna on 18 June 1979 by Presidents Jimmy Carter and Brezhnev and submitted shortly thereafter for ratification by the US Senate.
But renewed tension between the superpowers prompted Carter to withdraw the Senate treaty in January 1980, after the Soviet invasion of Afghanistan. However, the United States and the Soviet Union voluntarily complied with the weapons limits agreed in SALT II in subsequent years. Meanwhile, the new negotiations that began in 1982 in Geneva between the two superpowers have been called the Strategic Arms Reduction Talks (START).