War Plan Orange

Informal studies as early as 1906 covered a number of possibilities, from basing at Gibraltar or Singapore[1] (an idea revived by the British before World War II)[2] to "a quick trans-Atlantic dash" to the Pacific.

After mobilization (the ships maintained only half of their crews in peacetime), the fleet would sail to the western Pacific to relieve American forces in Guam and the Philippines.

Following the 1933 Operations IV Wargame, which resulted in defeat for a hypothetical blue fleet meant to symbolize a US Philippine relief force, War Plan Orange was revised to account for a more steady, methodical advance in order to take Japanese strongpoints in the Marshall Islands.

This was done in accordance to observations that both stretched logistical capacity in the "through ticket to the Philippines" strategy, and inability to repair damaged vessels, allowed Japan to gain command of the sea via the neutralization of the US battle line force.

While the Allies took extensive measures to combat the threat of German U-boats, the Japanese failed to effectively counter the American submarines which ultimately choked Japan's industrial production and paralyzed her navy.

Japan also notably failed to institute an anti-commerce campaign where systematic use of commerce raiders could have made Allied operations much more complex and conquering and holding Japanese-held islands more difficult.

American war planners failed to appreciate that technological advances in submarines and naval aviation had made Mahan's doctrine obsolete and did not anticipate a preemptive strike from the Japanese.

[11] A number of requirements grew out of Orange, including the specification for a fleet submarine with high speed, long range, and heavy torpedo armament.