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.
Air warfare of World War II resources into an escalating battle of attrition on the island, at sea, and in the sky, with eventual victory going to the Americans in February 1943. It was a campaign the Japanese could ill afford. A majority of Japanese aircraft from the entire South Pacific area was drained into the Japanese defence of Guadalcanal. Japanese logistics, as happened time and again, failed; only 20% of the supplies dispatched from Rabaul to Guadalcanal ever reached there. After 1942, the United States made a massive effort to build up its aviation forces in the Pacific, and began island-hopping to push its airfields