 In 1944, with the Japanese position in the Pacific deteriorating rapidly, the IJA mobilized over 500,000 men and launched Operation Ichi-Go, their largest offensive of World War II, to attack the American airbases in China and link up the railway between Manchuria and Vietnam.This brought major cities in Hunan, Henan and Guangxi under Japanese occupation.The failure of Chinese forces to defend these areas encouraged Stilwell to attempt to gain overall command of the Chinese army, and his subsequent showdown with Chiang led to his replacement by Major General Albert Coady Wedemeyer.