On March 23, 1983 Ronald Reagan gave his famous speech in which he challenged the scientific community to create means to destroy nuclear weapons instead of creating means to make more dangerous weapons. Instead of creating more nuclear weapons and continuing the arms race, Reagan wanted to do away with the dangerous weapons instead. Though instead of trying to destroy those already in place, he wanted to implement systems of protection against the enemy while keeping the nuclear bombs that were owned by the United States.
In 1984 the Strategic Defense Initiative Organization was brought about to oversea the development of the lasers and the computer technology that directed the lasers. As the Cold War tensions began to lessen, so did the threat of the Soviet Union sending nuclear warheads towards the United States. The SDI and the SDIO aimed to change their focus to smaller scale lasers that were meant to protect various areas of the country as opposed to the entire thing though at this time, this was more of a hope than a realization.
In 1987 the SDIO introduced the Strategic Defense System Phase 1 Architecture. This design enabled the SDIO to place sensors and weapons in space. These sensors and weapons were controlled by one system. It wasn't until 1991 that the United States began scaling down their weapons and sensors. The aim was to be ready for accidental attacks instead of worrying about an intentional threat from the Soviet Union.
The SDIO and the SDI were done away with in 1993 by President Clinton who wished to further pursue the smaller scale systems that were largely ground based instead of space based. In place of the SDIO, groups such as the Ballistic Missile Defense Organization were formed to enhance the ground based navigation systems and lasers. Once the Cold War ended there was less of a need for large space based systems.