Rather than elevate the Cold War competition into space, Washington and Moscow agreed to both tacit and formal constraints on extraterrestrial military activities. These agreements included the 1967 Outer Space Treaty, which bans the placement of weapons of mass destruction in space or on celestial bodies, and the 1972 Anti-Ballistic Missile Treaty, which prohibits interference with monitoring satellites. The Carter administration tried to expand these formal rules by proposing a total ban on antisatellite weapons in 1978, but the effort ultimately failed due to problems in defining the scope of the ban and in deciding how to verify compliance. A more narrow treaty might be feasible, one that bans only systems specifically designed to destroy satellites. But verifying that no new ASAT weapons are being produced would be difficult, as would be ensuring the destruction of hidden models.
Every administration save one, that is.
But SDI was never deployed. Instead, the Reagan administration was forced to argue, implausibly, that SDI would facilitate a cooperative transition in U.S.-Soviet relations. The Kremlin's concerns about SDI were compounded by the Reagan administration's pursuit of antisatellite weapons and its rejection of ASAT negotiations. The Reagan team argued that advanced antisatellite weapons were needed to redress an imbalance in ASAT technology favoring the Kremlin, to deter Soviet attacks, and to counter threats posed by other Soviet space systems. The Democratic-controlled Congress pushed back, however, passing amendments requiring ASAT negotiations and preventing flight tests.