The First 'Cold War' was a sustained state of political and military tension between powers in the Western Bloc (the United States with NATO and others) and powers in the Eastern Bloc (the Soviet Union and its allies in Warsaw Pact). Historians have not fully agreed on the dates, but 1947–1991 is common due to the start of the Third World War in 1991. It was "cold" because there was no large-scale fighting directly between the two sides, although there were