Upon the outbreak of conflict in World War I men were initially eager to volunteer for overseas service. However, as the war dragged on the number of new volunteers signing up declined. Several campaigns appealing for more volunteers failed to produce sufficient numbers to cover losses already sustained, so the then Prime Minister, W. M. (Billy) Hughes, decided to have a referendum on the issue of conscription. The issue caused deep divisions within Australia with large meetings held both for and against the idea of conscription. Many people thought positively of conscription as a sign of loyalty to Britain and believed that it would also support the men at the front. However, trade unions feared that their members might be replaced by foreign or female labour and opposed conscription. Yet others opposed it on moral or religious grounds. The women's vote was seen as important and campaign information from both sides targeted women voters. The first referendum (1916) was narrowly lost which caused further divisions and resulted in a split in the Australian Labor Party. Another vote in 1917 was also lost.The conscription debate was raised again in 1943 during World War II. However, rather than risk a referendum on the issue Prime Minister Curtin allowed the Labor Party to debate the decision to allow Australian troops to fight beyond the current areas where Australian troops could be sent on active service. The Act was changed with little opposition expressed which thus avoided the divisiveness and bitterness of the 1916/1917 referenda. During the Vietnam War the National Services Act (1964) introduced compulsory National Service for 20-year-old males, with the selection process based on a ballot related to date of birth. Widespread opposition to conscription escalated during the late 1960s including campaigns by various womens groups such as the Save our Sons (SOS) organisation. Following the election of the Australian Labor Party to Federal Government on December 2nd 1972 conscription was ended on December 5th, 1972. To date there has not been any further conflicts in which Australian conscripts have been forcibly recruited.