For much of its history the Australian Army has been derivative of other armies, especially the British Army, and nowhere was this more evident than in the army's doctrine. In the twenty years after the end of the Second World War, army doctrinal thinking was impeded by three often competing influences: conflicting strategic interests, the continual borrowing of other countries' doctrines, and a practical emphasis on small-unit operations. During the war in the Pacific, in the almost literal absence of the British and fighting in theatres close to home, the Australian Army developed a distinctive national doctrine for conventional jungle warfare, but in the immediate aftermath of the war this was thrown over in favour of British doctrine and the contingency of service in traditional theatres of imperial interest, principally the Middle East. The pentropic experiment of the late 1950s-early 1960s saw the army adopt a modified American doctrine while nonetheless retaining elements of British conventional thinking. By 1965, with pentropic organisation abandoned and the commitment to Vietnam beckoning, doctrine had come full circle with the return to a focus on small-unit operations in the jungle. For much of the period under review, there was a mismatch between Australia's strategic outlook and its operational doctrine, one only finally resolved after the withdrawal from Vietnam.