President Nixon and General Secretary Brezhnev signed the historic ABM Treaty and the Strategic Arms Limitation Treaty on May 26, 1972, during the high-stakes Moscow Summit. This landmark agreement marked the first time the two global superpowers agreed to cap their escalating nuclear arsenals. To ensure the world trusted the agreement, the treaty secretly authorized the use of spy satellites for verification, legally codifying space-based espionage for the very first time under international law.
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