Origins of the Cold War
Australia's entry into the Cold War came in 1950, when it rushed combat air and sea forces into the Korean War, two days after the Americans did. The Australian Prime Minister received a hero's welcome in Washington. The ANZUS military alliance with New Zealand and the United States was signed in July 1951; it was a plan for consultation and did not involve military planning like NATO. Public opinion in Australia was intensely hostile to Japan after its wartime atrocities, but Japan was now an ally in the Cold War, so Australia's accepted the very generous soft peace treaty with Japan in 1951. Instead of worrying about a resurgent Japan, Australia now worried more about a possible Chinese threat.
20th-century events
Two wars and a near-war in the 1950s became the focus for capitalist versus communist struggle. The first war was the Korean War, fought between People's Republic of China-backed North Korea and mainly United States-backed South Korea. The Korean Peninsula was a Japanese colony between 1910 and 1945, when Soviet and American troops invaded and divided it along the 38th parallel. A communist government controlled the territory north of the border and a capitalist one controlled the South, with both authorities considering the other one illegitimate and claiming sovereignty over the entire peninsula. North Korea's invasion of South Korea on June 25, 1950 led to United Nations intervention. General Douglas MacArthur led troops from the United States, Canada, Australia, Great Britain, and other countries in repulsing the Northern invasion. However, the war reached a stalemate after Chinese intervention pushed U.N. forces back, and an ended hostilities in July 1953, leaving the two Koreas divided and tense for the rest of the century.