Chiang, however, had become increasingly agitated over the course of the Battle of Shanghai, even angrily declaring that he would stay behind in Nanking alone and command its defense personally. But just when Chiang believed himself completely isolated, General Tang Shengzhi, an ambitious senior member of the Military Affairs Commission, spoke out in defense of Chiang's position, although accounts vary on whether Tang vociferously jumped to Chiang's aid or only reluctantly did so. Seizing the opportunity Tang had given him, Chiang responded by organizing the Nanking Garrison Force on November 20 and officially making Tang its commander on November 25. The orders Tang received from Chiang on November 30 were to "defend the established defense lines at any cost and destroy the enemy’s besieging force".