no longer had power in the region. This added to their sense of vulnerability. The United States was initially reluctant, offering instead an informal guarantee of protection. But the need to strengthen the West against communism grew with the Communist victory in the Chinese Civil War in 1949 and the 1950-1953 Korean War. Additionally, the United States wanted to gain Australian and New Zealand approval for a 'soft peace' with Japan. The treaty allayed antipodean fears that such a peace would allow Japan to threaten them again. The resulting treaty was concluded at San Francisco on 1 September 1951, and entered into force on 29 April 1952. The treaty bound the signatories to recognise that an armed attack in the Pacific area on any of them would endanger the peace and safety of the others. It stated 'The Parties will consult together whenever in the opinion of any of them the territorial integrity, political independence or security of any of the Parties is threatened in the Pacific'. The three governments also pledged to maintain and develop individual and collective capabilities to resist attack. Korea, Malaysia, Borneo, Vietnam, and the War on Terror The treaty itself was not a source of debate for over 30 years, with New Zealand participating as part of the British Commonwealth Forces in the Korean War and the Malayan Emergency, followed by the Indonesia–Malaysia confrontation, and directly as part of ANZUS in the Vietnam War. The Vietnam War was the first conflict New Zealand entered that did not involved the British or any other Commonwealth countries outside of Australia. As an ANZUS member New Zealand contributed military and non military assistance to the United States war effort in Vietnam from 1963 until 1975. New Zealand and Australian combat forces were withdrawn in 1972 and New Zealand non-military medical aid continued until 1975. In response to the War in Afghanistan, New Zealand sent transport aircraft, maritime patrol aircraft, and frigates to the Persian Gulf, as well as a very small number of soldiers, SAS soldiers, medical and assorted and peace-keeping forces, to Afghanistan in 2001. Despite Prime Minister Helen Clark being openly critical of American justifications for the 2003 Iraq war, New Zealand did send engineer troops to Iraq following the 2003 invasion. These troops were however officially engaged in reconstruction under UN Security Council Resolution 1483 and were non-combatant. Australian reservations about the MX missile In