自一九七二年美苏签署反导条约以来,美国就放弃了战略武器防御系统的研制。然而,从那时起苏联则加强了反导和防空工作,而美国仅维持在一个低的水平上。由于逐渐认识到在今后两三年内苏联第一次核打击可能给美国造成的破坏,美国国会和国防部又 Since the United States and the Soviet Union signed the ABM Treaty in 1972, the United States has given up the development of a strategic weapon defense system. Since then, however, the Soviet Union has stepped up its anti-ballistic missiles and air defense work, while the United States has only maintained a low standard. With the gradual realization of the potential damage the United States could be caused by the first nuclear strike by the Soviet Union in the next two to three years, the U.S. Congress and the Department of Defense