In the 1970s, with the cold war between the United States and the Soviet Union, Sino-Soviet relations deteriorated. At that time, the United States suffered an energy crisis, and then US President Nixon visited China, and China and the United States established diplomatic relations from 65438 to 0979. In the 1980s, Sino-US relations further deepened. In the 1990s, Sino-US relations deteriorated. By 2 1 century, under the background of economic globalization, Sino-US relations tend to be normalized.