Military Hardware: Tanks, Bombers, Submarines and More The U.S. Spent 7 Years Developing a Nuclear-Powered Cruise Missile That Could Carry 12 Thermonuclear Warheads — Then Cancelled It In 1957, the U.S. Air Force began Project Pluto — a nuclear-powered cruise missile program. The result was the Supersonic Low Altitude Missile (SLAM).... Isaac Seitz1 hour ago