The first few years of the 1970s were marked with tremendous progress for China's relations with the U.S. In July and October 1971, Dr. Henry Kissinger, then national security adviser to the president of the U.S., visited China to pave the way for President Richard Nixon. After that, Nixon visited China on February 21, 1972, and he became the fist sitting U.S. president to visit the People's Republic of China.