It has taken America’s leaders a long time to learn the lessons of nuclear weapons. President Harry Truman, who took the decision to bomb Hiroshima and Nagasaki called the atomic bomb the “greatest thing in history.” Almost 20 years later, with America having lost its nuclear monopoly, trapped in a desperate growing arms race with the Soviet Union, and having survived a crisis that threatened nuclear war, President John F. Kennedy described the bomb as having turned the world into a prison in which man awaits his execution. Fast forward another two decades, under pressure from peace movements, President Ronald Reagan agreed with Soviet leader Mikhail Gorbachev that the superpowers should eliminate all nuclear weapons.