The outbreak of the Manchuria 918 Incident and the Shanghai 128 Incident, in 1931 and 1932 respectively, demonstrated that China's military power was significantly inferior to Japan's. Among domestic stability operations, in order to ready its armed forces against Japan, the Chinese Nationalist government worked on acquiring arms and military assistance from Germany through China-Germany barter trade agreements. Such military procurement included forces reorganization and training programs, arms sales, defense industry improvement, and defense infrastructure fortifications. Prior to the Marco Polo Bridge Incident in 1937, it showed that China's military strength still remained far behind Japanese, however, the aforementioned German military assistance to China offered Japanese scholars awareness that Japanese invasion might be a mistake. It further proved that Chinese armed forces were able to delay Japanese invasion and become a critical power for Ally's counter operations.