The Sino-Soviet dispute of the late 1950s was the most important development in Chinese foreign relations. The Soviet Union had been China's principal benefactor and ally, but relations between the two were cooling. The Soviet agreement in late 1957 to help China produce its own nuclear weapons and missiles was terminated by mid-1959. From that point until the mid-1960s, the Soviets recalled all of their technicians and advisers from China and reduced or canceled economic and technical aid to China. The discord was occasioned by several factors. The two countries differed in their interpretation of the nature of "peaceful coexistence." The Chinese took a more militant and unyielding position on the issue of anti-imperialist struggle, but the Soviets were unwilling, for example, to give their support on the Taiwan question. In addition, the two communist powers disagreed on doctrinal matters. The Chinese accused the Soviets of "revisionism"; the latter countered with charges of "dogmatism." Rivalry within the international communist movement also exacerbated Sino-Soviet relations. An additional complication was the history of suspicion each side had toward the other, especially the Chinese, who had lost a substantial part of territory to tsarist Russia in the mid-nineteenth century. Whatever the causes of the dispute, the Soviet suspension of aid was a blow to the Chinese scheme for developing industrial and high-level (including nuclear) technology.
