The estrangement of Maoist China from the Soviet Union in the early 1960's destroyed the bipolar political alignment which had prevailed in the world since the end of the Second World War.
Platte, William A.
"Peking, Moscow, and the SALT Talks,"
Naval War College Review: Vol. 23
, Article 11.
Available at: https://digital-commons.usnwc.edu/nwc-review/vol23/iss5/11