Operations in Burma were the centerpiece of the China-Burma-India (CBI) Theater. This was the U.S. military designation during the war for the China and Southeast Asia. Operational command of Allied forces (including U.S. forces) in the CBI was officially the responsibility of the Supreme Commanders for South East Asia or China. However, U.S. forces, in practice, were usually overseen by General Joseph Stilwell, the Deputy Allied Commander in China. For the U.S., the CBI’s importance came from its logistical and support mission, in supporting China and British elements in the war through the logistical capability of the American forces. U.S forces in the CBI included the Flying Tigers (later the 14th Army Air Force) and transport units of the Tenth Army Air Force flying the ‘Hump’ into China, the 1st Air Commando Group, the engineers who built the Ledo Road, and the 5307th Composite Unit (Provisional), popularly known as 'Merrill’s Marauders.'