Operation Matterhorn - Plan

Plan

The idea of basing the Superfortresses in China first surfaced at the Casablanca Conference in January 1943. While planners assessed this option, the Anglo-American Combined Chiefs of Staff, meeting in Quebec in August, authorized a central Pacific drive that included the seizure of the Mariana Islands. Not only were the Marianas closer to Tokyo, but once in Allied hands they could be supplied and defended more easily than other sites. In September, Combined Chiefs of Staff planners concluded that B-29s in China would be plagued by logistical problems. However, President Franklin D. Roosevelt decided in favor of the China bases because he was impatient to bomb Japan and wished to bolster the Chinese war effort. At the Sextant Conference in Cairo at the end of the year, he promised Chiang Kai Shek that the very heavy bombers would be coming to his country. General Henry H. Arnold supported that decision as a temporary expedient, but still preferred strategic missions against Japan from the Marianas, once bases there were available.

Operation Matterhorn was developed by Brig. Gen. Kenneth B. Wolfe in October 1943 for implementation by the XX Bomber Command. Wolfe drew from an initial plan termed "Setting Sun" based on an outline drawn by President Franklin D. Roosevelt at the Casablanca Conference and from a counter-plan offered by Gen. Joseph Stilwell called "Twilight". (The primary difference between the two was that Chennault proposed that the B-29s be permanently based in India and forward-based in China.) The forward airbases in China would be supplied out of India by the flying supplies over the Hump. Under Setting Sun, the forward bases were to be in Guangxi in southern China, but because of intense Japanese pressure against the forces commanded by Stilwell and Gen. Claire Chennault, the Matterhorn plan moved the bases farther inland to Chengdu.

General Arnold approved the plan on October 12 and presented it to the U.S. Joint Chiefs after convincing President Roosevelt, through Gen. George C. Marshall as an intermediary, that no other strategic bombing of Japan was possible until the capture of the Mariana Islands, which was not yet scheduled. Roosevelt was unhappy with the projected starting date of June 1, 1944, having promised Chiang Kai-Shek that the campaign would begin January 1, 1944, but he agreed on condition that the campaign be continued for a year.

The key development for the bombing of Japan was the B-29, which had an operational range of 1,500 miles (2,400 km); almost 90% of the bombs dropped on the home islands of Japan were delivered by this type of bomber.