Political map of Australia, New Zealand & the Southwest Pacific 01 September 1951 (ANZUS): By August 1950, the nationalists were in control of Indonesia, replacing the United States of Indonesia (United States of Indonesia) with a unified Republic (Republic of Indonesia). Meanwhile the Korean War (Korean War) had broken out, bringing the Cold War (Cold War) which had been brewing between the United States and the Soviet Union into full swing. To shore up the defence against communism in the South Pacific, the US signed the ANZUS Pact with Australia and New Zealand in 1951 (ANZUS).