The Singapore strategy was a series of war plans that evolved over a twenty-year period in which the basing of a fleet at Singapore was a common but not a defining aspect. Plans were crafted for different contingencies, both defensive and offensive. Some were designed to defeat Japan, while others were merely to deter aggression.
In November 1918, the Australian Minister for the Navy, Sir Joseph Cook, had asked Admiral Lord Jellicoe to draw up a scheme for the Empire's naval defence. Jellicoe set out on a tour of the Empire in the battlecruiser HMS New Zealand in February 1919. He presented his report to the Australian government in August 1919. In a section of the report classified as secret, he advised that the interests of the British Empire and Japan would inevitably clash. He called for the creation of a British Pacific Fleet strong enough to counter the Imperial Japanese Navy, which he believed would require 8 battleships, 8 battlecruisers, 4 aircraft carriers, 10 cruisers, 40 destroyers, 36 submarines and supporting auxiliaries.
Although he did not specify a location, Jellicoe noted that the fleet would require a major dockyard somewhere in the Far East. A paper entitled "The Naval Situation in the Far East" was considered by the Committee of Imperial Defence in October 1919. In this paper the naval staff pointed out that maintaining the Anglo-Japanese Alliance might lead to war between the British Empire and the United States. In 1920, the Admiralty issued War Memorandum (Eastern) 1920, a series of instructions in the event of a war with Japan. In it, the defence of Singapore was described as "absolutely essential". The strategy was presented to the Dominions at the 1923 Imperial Conference.
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Quo Fata Vocant-Whither the Fates call