Guam

Guam. The largest of the Pacific Marianas, this island, ceded to the USA in 1898, was occupied by the Japanese at the start of the Pacific war and put under navy administration. In July 1944 it was recaptured by Maj-General Roy Geiger's 55,000-strong 3rd US Amphibious Corps. Guam contains some of the Pacific's most difficult terrain in its 55 km. (34 mi.) length, and at the time it possessed the only adequate water supply in the Marianas, and the best harbour. It was therefore vital to the Americans as an advanced base to begin the second Philippines campaign and to permit US aircraft to start the strategic air offensive against Japan. The landings by the 3rd Marine Division and the 1st Provisional Marine Brigade, with 77th Infantry Division in reserve, were delayed until 21 July because Saipan had taken longer than expected to capture; and because approaching Japanese surface forces had first to be defeated (see Philippine Sea).

The delay enabled the Japanese garrison of 19,000 troops to construct the most formidable beach defences, a way through which had to be cleared by underwater demolition teams (see frogmen). But the delay also allowed US support forces to deliver the most meticulous, intensive, and prolonged air and sea bombardment the Japanese received during the Pacific war. As a result, Japanese resistance was sporadic and uncoordinated, and 10,646 were killed, ten times the US losses. But the survivors kept fighting and it took three weeks to occupy the whole island. Mopping-up operations continued throughout the remainder of the war, and beyond it: the last Japanese soldier hiding there did not surrender until 1972.