As part of Japan’s strategy to expand its sphere of influence into the western Pacific and Southeast Asia, the US territory of Guam was targeted for invasion upon Japan’s entry into the war. Prior to the Japanese attack on 8 December, the US Congress had declined requests for reinforcements to Guam as they saw the difficulty of defending the island, given its position amongst the Japanese-held Mariana Islands. The US forces stationed on the island totalled little more than 500 marines and naval personnel with a small group of semi-trained locals. The only artillery available was aboard USS Penguin, a refitted World War I-era minesweeper, which was badly damaged and scuttled soon after the Japanese aerial attack on 8 December. Following bombing runs by Japanese aircraft on 8 and 9 December, an invasion force of nearly 6,000 Japanese troops landed at various points around the island on 10 December, forcing the US troops to surrender after brief resistance.
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