How did the Japanese attack on nanjing gain favor for the communist leader Mao Zedong?

The Japanese attack on Nanjing in 1937 created widespread chaos and suffering, which discredited the Nationalist government led by Chiang Kai-shek in the eyes of the Chinese populace. Mao Zedong and the Communist Party positioned themselves as defenders of the people against both Japanese aggression and Nationalist corruption, gaining support as they provided aid and organized resistance. The atrocities committed during the Nanjing Massacre highlighted the need for a strong alternative leadership, allowing Mao to strengthen his influence and recruit more followers. This shift in public sentiment ultimately bolstered the Communist movement during the Chinese Civil War.