Which nation did more to escalate the tensions of the cold war, the united states or the soviet union?

The relations between the United States of America and the Union of Soviet Socialist Republics (1922-1991) succeeded the previous relations from 1776 to 1917 and predate today's relations that began in 1992. Full diplomatic relations between the two countries were established late due to mutual hostility. During World War II, the two countries were briefly allies. At the end of the war, the first signs of post-war mistrust and hostility began to appear between the two countries, escalating into the Cold War; a period of tense hostile relations, with periods of détente.