In a landmark address to the nation, President Ronald Reagan unveiled his vision for the Strategic Defense Initiative (SDI), a proposed missile defense system designed to protect the United States from potential nuclear missile attacks. Reagan articulated his belief that the United States needed a robust defense mechanism capable of intercepting enemy missiles before they could reach American soil. This ambitious program aimed at utilizing advanced technologies including space-based systems to monitor and engage incoming threats, essentially creating a protective shield against nuclear bombardment.

The proposal came in the context of heightened tensions during the Cold War, particularly with the Soviet Union's nuclear arsenal expanding. Reagan's speech highlighted the urgency of the situation, presenting SDI as not just a military initiative but as a means to promote peace and global security. The program garnered significant attention and controversy, with mixed reactions from both political spheres and the public. Critics questioned the technological feasibility and the potential to escalate the arms race, while proponents viewed it as a crucial step towards safeguarding the nation.

As the primary goal of SDI was to develop a missile defense system that could effectively neutralize threats, it represented a significant shift in U.S. defense policy. Reagan's proposal suggested that instead of simply relying on the deterrence doctrine of Mutual Assured Destruction (MAD), the nation could seek to render enemy missiles ineffective through technological advancements. This announcement set the stage for extensive research and development efforts in missile defense technology, influencing U.S. military strategy for years to come.