American-British-Dutch-Australian Command

The American-British-Dutch-Australian (ABDA) Command, or ABDACOM, was a short-lived, supreme command for all Allied forces in South East Asia, in early 1942, during the Pacific War in World War II. The main objective of the command, led by General Sir Archibald Wavell, was to maintain control of the "Malay Barrier" (or "East Indies Barrier"), a notional line running down the Malayan Peninsula, through Singapore and the southernmost islands of Dutch East Indies. ABDACOM was also known in British military circles as the "South West Pacific Command", although it should not be confused with the later South West Pacific Area command (see below).

Although ABDACOM was only in existence for a few weeks and presided over one defeat after another, it did provide some useful lessons for combined Allied commands later in the war.

Efforts to organise the ABDA Command began soon after war between the Allies and Japan commenced, on 7 December 1941. It was finalized at the Arcadia Conference in Washington. On December 29, Winston Churchill said that it had been agreed Wavell would be supreme commander. Wavell then held the position of British Commander-in-Chief, India. Churchill added:

Following the declaration by the four nations on 1 January 1942, the Allied governments formally appointed Wavell. The formation of ABDACOM meant that Wavell had control of a huge, but thinly spread force, covering an area from Burma in the west, to Dutch New Guinea and the Philippines in the east. Other areas, including India and Hawaii, remained officially under separate commands, and in practice General Douglas MacArthur was in complete control of Allied forces in the Philippines. At Wavell's insistence, the western half of northern Australia (see map) was added to the ABDA area. The rest of Australia was under Australian control, as were its territories of Papua and New Guinea.

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