Operation Hailstone
In World War II, Japanese-held Yap was one of the islands bypassed in the U.S. "Leapfrogging" strategy, although it was regularly bombed by U.S. ships and aircraft, and Yap-based Japanese bombers did some damage in return. The Japanese garrison comprised 4,423 Imperial Japanese Army men under the command of Colonel Daihachi Itoh and 1,494 Imperial Japanese Navy men. A significant portion of the Japanese fleet was based in Truk Lagoon. In February 1944, Operation Hailstone, one of the most important naval battles of the war, took place at Truk, in which many Japanese support vessels and aircraft were destroyed.