Scientists discovered nuclear energy at the end of the nineteenth century. Within fifty years it became a decisive factor in our war with Japan and has affected international arms policies ever since. The study of nuclear energy began in the nineteenth century when Marie and Pierre Curie discovered the radioactive elements radium and polonium. Before this only uranium and thorium were the only radioactive elements that were known. Radium and polonium were hundreds of times …showed first 75 words of 1495 total…

…showed last 75 words of 1495 total…announced the Strategic Defense Initiative (SDI), dubbed Star Wars by the press, a satellite-based defense system that would destroy incoming missiles and warheads in space. In, 1985, Mikhail Gorbachev became the leader of the Soviet Union. He made a plan for the United States and the Soviet Union to cut down their nuclear arms. It also called for the end of the space strike weapons (Star Wars). This among other things ended the Nuclear Arms Race.