SDI (Strategic Defense Initiative)

The Strategic Defense Initiative (SDI) was a proposed U.S. program in the 1980s aimed at developing a missile defense system to protect the country from nuclear missile attacks, particularly from the Soviet Union. Announced by President Ronald Reagan in 1983, SDI envisioned using ground-based and space-based technologies, such as lasers and satellites, to intercept incoming missiles before they could reach their targets. While the initiative sparked much debate and criticism regarding its feasibility and costs, it represented a shift in U.S. defense strategy during the Cold War, emphasizing active defense over deterrence. The program was never fully implemented.