How did the Japanese invasion help unify the Chinese temporairly?

The Japanese invasion of China during World War II helped unify the Chinese temporarily by creating a common enemy that all Chinese factions could resist together. The atrocities committed by the Japanese troops fueled a strong sense of nationalism among the Chinese population, leading to increased cooperation between different political groups and factions within China to fight against the common enemy. This temporary unity was exemplified by the formation of a united front between the Chinese Nationalists and Communists to resist the Japanese invasion.