of 1942. Blamey was appointed Commander-in-Chief (C-in-C) in March 1942; in April a major re-organisation took place: the name First Army —which previously referred to a Militia formation—was reassigned to I Corps, which was expanded to army size with the inclusion of Militia divisions. The First Army's initial area of responsibility was the defence of Queensland and northern New South Wales. The Second Army was responsible for south-eastern Australia; the other components of Australia's defences were III Corps (in Western Australia), the Northern Territory Force and New Guinea Force. Conscription was effectively introduced in mid-1942, when all men 18–35, and single men aged 35–45, were required to join the CMF. In addition, the Army's armoured force was greatly expanded. In February 1942, a change in regulations meant that if 65% of the official, establishment strength of a Militia unit, or 75 per cent of the actual personnel, volunteered for the AIF, the unit became an AIF unit. At the time, the CMF were often scorned as "chocolate-tin soldiers", or "chockos", because it was thought they would melt in the heat of battle. Nevertheless, Militia units distinguished themselves and suffered extremely high casualties during 1942, in New Guinea, which was then an Australian territory. The prime example was the 39th (Militia) Battalion, many of them very young, untrained and poorly equipped, who distinguished themselves and suffered heavy casualties, in the stubborn rearguard action on the Kokoda Trail. By late 1942, the 7th Division was beginning to relieve the Militia in New Guinea. In August, as the Kokoda battles raged, Militia and 7th Division units formed the bulk of Australian forces at the Battle of Milne Bay, the first outright defeat inflicted on Japanese land forces. The 6th and 7th Divisions, with Militia units and elements of the 1st Armoured, formed a large part of Allied forces which destroyed the major Japanese beachhead in New Guinea, at the Battle of Buna-Gona. In 1943, the Defence Act was changed to allow Militia units to serve south of the Equator in South East Asia. The 9th Division remained in North Africa and distinguished itself at the Second Battle of El Alamein, after which victory over Erwin Rommel was assured, and returned to Australia in 1943. Later that year it was pitched into battle against Japanese forces in New Guinea. General Douglas MacArthur, the Supreme Allied Commander in the South West Pacific, was resented for