During the Korean War, the integration of the Royal Australian Navy (RAN) and Royal Navy (RN) was achieved with relative ease, but the involvement of the United States Navy (USN) presented a number of challenges. The RAN's commitment to the Vietnam War represented a definitive break in its history. During the first fifty years of its existence, the RAN reverted to RN control during the First World War, was initially placed on a war footing as a result of Britain's Imperial War Telegram during the Second World War and also served within a Commonwealth command structure during the Korean War, Malayan Emergency and the Indonesian Confrontation. Britain's decision not to participate in the Vietnam War meant that the RAN was required to integrate directly with the USN. The USN's post-Second World War involvement in Vietnam commenced during the French-Indochina conflict, which raged between 1946 and 1954.