Japanese air attacks on the Mariana Islands and anti-aircraft guns shot down about 37 Japanese aircraft during these raids. After the Marianas began to come under attack, the United States military stepped up its raids on the Japanese-held islands which could be used to launch raids on the B-29 bases. Particular attention was given to Iwo Jima, as it was correctly assumed that the Japanese aircraft which attacked the Marianas were flying from Japan and staging through the island en route to their targets. Following the first raid against Saipan in November, XXI Bomber Command B-29s were dispatched against Iwo Jima's airfields on November 5 and 8.
Japanese air attacks on the Mariana Islands the Mariana and Palau Islands campaign. These islands were needed to provide bases for USAAF Twentieth Air Force B-29 Superfortress heavy bombers to attack the Japanese home islands. Construction of the large air bases needed to support B-29s began on Saipan in June 1944, before the end of the Battle of Saipan, and work on air fields on Tinian and Guam commenced in July and August respectively. The B-29s of the XXI Bomber Command began to arrive at Saipan starting on October 12, and the 73rd Bombardment Wing began flying warm-up missions against Japanese-held islands in the Pacific on October