Nixon had many accomplishments in the foreign policy arena. He opened a new era of relationship between the United States and China. Nixon was the first president to visit China, a country with which the U.S. had no diplomatic relations. Nixon and Chinese leader Mao Tse-tung appeared together in public, a sight many would never have predicted given the hostilities between the two nations. The breakthrough in U.S.-China relations arguably forced the Soviet Union to come to the table with the United States because it feared a better relationship between the two powers that were its greatest rivals. This culminated in President Nixon and Soviet leader Leonid Brezhnev signing the Strategic Arms Limitations Talks, called SALT. Under this agreement, the superpowers agreed to curtail missile development and slow the arms race that seemingly threatened world peace.