These raids targeted United States Army Air Forces (USAAF) bases and sought to disrupt the bombing of Japan by Boeing B-29 Superfortress heavy bombers operating from the islands.

While the decision to invade Iwo Jima had been made before the raids commenced, stopping the attacks formed part of the justification for the landing.

The USAAF's Seventh Air Force played the most important role, and continuously attacked the Japanese-held islands until just before the end of the war.

The Thunderbolts were also responsible for suppressing the Japanese-held Mariana Islands, though it proved difficult to stop the 3,600-man garrison from repairing the airfield on Pagan.

[8][9] The head of the USAAF General "Hap" Arnold, who also directly commanded the Twentieth Air Force, was concerned about whether these defenses were sufficient, particularly given the high cost of the Superfortress bombers.

Small numbers of Japanese aircraft flying from Guam, Peleliu, Iwo Jima and Truk made occasional raids on the American forces on Saipan during the fighting there, but caused little damage.

[15] Small numbers of Japanese soldiers who had avoided capture at the end of the battles on the islands also raided the B-29 bases on occasion, mainly in search of food.

[17][18] On November 3 the Imperial General Headquarters issued a statement which falsely claimed that Japanese aircraft had bombed and destroyed fifteen locations in Saipan and Tinian.

During the early hours of November 27, two G4Ms flying from Iwo Jima struck Isley Field from low altitude and escaped after destroying one B-29 and damaging eleven others.

[10] Later that day, twelve bomb-equipped Mitsubishi A6M "Zero" fighters from the IJN's 252 Kōkūtai (252 Air Group) accompanied by two Nakajima C6N "Myrt" reconnaissance aircraft for navigation purposes departed Iwo Jima for Saipan.

The attackers flew just above sea level to avoid US radar, and one of the A6Ms was forced to divert to Pagan after its propeller struck a wave; this aircraft was shot down by a USAAF Thunderbolt while attempting to land.

Arnold became frustrated that the MEW still was not in use, and on December 3 Fleet Admiral Chester W. Nimitz, the commander of the Pacific Ocean Areas, ordered that the highest priority be given to installing the radar.

[39] In early February the 6th Air Army's parent headquarters, the General Defense Command (GDC), reached the conclusion that the raiding forces being dispatched against the American bomber bases were too small to be effective.

As it was not possible to allocate additional aircraft to bolster these missions, the GDC directed that the offensive cease and that the 6th Air Army be held in reserve to be used against any Allied forces which landed in the Japanese home islands.

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.

[43] Nimitz ordered a major attack on Iwo Jima following the raids of November 27 and dispatched Lieutenant General Millard Harmon, the commander of Army Air Forces in the Pacific Ocean Areas, from Hawaii to Saipan to oversee this operation.

Due to cloud cover over Iwo Jima the heavy bombers were forced to use radar rather than visual bombing, which limited the effectiveness of these attacks.

While the attacks on Iwo Jima damaged the island's airfields, the Japanese managed to keep at least one of them operational at all times, and none were closed for more than a single day.

[46][47][48] The need to repair damage to the airfields forced the Japanese garrison on Iwo Jima to divert labor from building defensive positions, however.

[49] The combination of heavy losses over Saipan and damage to the airfields on Iwo Jima caused the Japanese to break off their attacks against the Marianas on 2 January.

A 136-man force designated the Giretsu Airborne Unit was formed for this suicide mission, which called for the destruction with explosive charges of B-29s by troops carried by Mitsubishi Ki-21 "Sally" bombers.

The commandos undertook intensive training at Saitama Kanto and the raid was scheduled to take place on January 17, 1945, but was canceled after damage to the airfields at Iwo Jima.

[52] Following the perceived success of the raid on Okinawa the IJN developed plans for a force of naval commandos to attack airfields in the Marianas.

The commandos and G4Ms selected to land in the Marianas conducted intensive training at bases in northern Honshu and the operation was scheduled for late July.

[56] However, this was not necessary due to the success of the Seventh Air Force and the USN's campaign against Iwo Jima's airfields as well as the Japanese military's shortage of long-ranged aircraft.