Guam was a bustling island of nearly 500,000 troops. Japanese forces had captured the island in December 1941, and the United States had retaken it two and a half years later after three weeks of bloody fighting. During the invasions of Iwo Jima and Okinawa, transport ships carrying thousands of troops had left this harbor day and night for a week, bound for the beachheads more than 1,200 miles to the north.
