The island of Okinawa is located just 350 miles from Japan’s southern island of Kyushu, and it would be the target of Operation ICEBERG. The American Joint Chiefs of Staff planned ICEBERG as their next step in the push toward the Home Islands. They hoped to pressure Imperial Japan to surrender. It would also be the place to stage the upcoming invasion of the Japanese Home Islands. The invasion of Okinawa was delayed by the prolonged fighting on Iwo Jima, and lasted for three months. It was a bloody battle, the worst of the Pacific War. The Japanese were continuing their “war of attrition” strategy demonstrated at Peleliu and Iwo Jima. They were determined to make the war as costly for the Americans as possible. By the time the battled ended, more than 250,000 Americans, Japanese, and civilian Okinawans had been killed.

Marine Colonel Francis I. Fenton kneels and prays at the foot of his son's grave, while bereaved friends stand reverently by. From the Norm Hatch Collection at the National Museum of the Pacific War

The Joint Chiefs used the high casualty numbers from Iwo Jima and Okinawa to estimate the cost of an invasion of the Home Islands. Tens of thousands of Americans had been killed, and nearly 100,000 Japanese soldiers died defending an island they knew they could not keep. As brutal as the fight for Okinawa had been, the Americans knew the price of taking Japan would be even greater.

  • 77th Infantry Division Newspaper

77th Infantry Division Newspaper

Special Battle Edition of 77th Infantry Division newspaper, “The Liberty Torch” published in Ryukyu Islands during the Battle for Okinawa. The headline proclaims “IE SHIMA STEPPING-STONE TO JAPAN.” Ie Shima was one of the smaller islands surrounding Okinawa. The Joint Chiefs of Staff planned to push rapidly through the Japanese territories of Iwo Jima and Okinawa before invading the southernmost island of Kyushu in the Japanese island chain. The cost of taking those two islands, however, was incredible. The civilian casualties, in particular, gave military leaders pause. Many Okinawans had been pressed into military service for the Japanese or simply caught in the crossfire of the battle. With the civilian population of Kyushu, the casualties could be expected to be even higher.

Manpower would also be an issue for the upcoming invasion of Japan, codenamed DOWNFALL. Tens of thousands of veterans were killed or wounded on Iwo Jima and Okinawa, and as the war dragged, many servicemen with valuable experience had accrued enough points to return home. The men filling the vacated positions were newer recruits with little to no battle experience. As military planners realized the sheer magnitude of bloodshed that would come from Operation DOWNFALL, they began to consider their alternative: the atomic bomb.