Not having read all the posts, nor the links to other posts I might be simply regurgitating what has already been covered. But that said it goes back further than just this WW2 period of time.

In 1894, China was sliding into national chaos as the Manchu dynasty lost control of the hinterlands, and then the "upstart" nation of Japan defeated China in a brief and humiliating war. When the Manchu dynasty finally collapsed into anarchy completely, Sun Yet-Sen returned in 1911 to China from his second exile and attempted to unite the nation in a democratic model. Sadly Sun couldn’t make it work went into a third exile, and China again fell into territorial warlord rule. During this short period, Japan was engaged in WW1 as an Allied Force fighting the Central Powers, so the Japanese left China to its own resources. In another twist of fate, Hirohito became the Japanese Emperor on the death of his father in December of 1926, and shortly thereafter the reasonably moderate and democratic Diet (Japanese Parliament) lost influence to the militarists with the new Emperor.

Back in China, it wasn’t until 1923 that Sun could get any cohesion in the nation, and he was supported by the warlords ironically. Unfortunately Sun Yet-Sen died less than two years later on March 12th, 1925 in Beijing, and then thing got even more divided for China. There were two factions vying for power; as Sun himself had sought and received support from the Communist International in Moscow, and their number one representative in China (Mao) was included in a formula by which a number of individual communists could enter the Kuomintang as members. In return, the new Soviet Union provided Sun with military advisers, arms, ammunition and technical help in strengthening his political organization.

This didn’t sit very well with the many of the "upper class" Chinese, especially a man who was an up and coming military leader, and who would marry Sun’s sister-in-law (one of the Soong sisters), one Chiang Kai-shek. The warlords didn’t like the idea of giving any power to the peasant workers, and the militaristic Chaing was equally displeased with the idea. But he also didn’t want any warlord bandits around, so first he led a combined army of Nationalists and Communists against the warlords and defeated them by late 1927 and recruited their troops into his army. Then Chiang turned on the Communists with a vicious purge that sent Mao and his colleagues into the shelter of diverse remote base areas.

This situation remained an on-again, off-again guerrilla affair until 1934 when Chiang decided that destroying the domestic "enemy of the heart" was more important than confronting the "enemy of the skin" (Japanese) who had begun their aggressions against China itself in 1931.

By 1934 the Chinese Communist forces, having been soundly defeated in Kiangsi, retreated north and west 2,500 to 3,000 miles through mountainous country to the Shensi area. They remained in constant battle with Chiang’s Nationalist Komintang forces as they retreated.

As a consequence the Communists suffered between 150,000 to 170,000 casualties and defections of the approximately 200,000 who originally started the Long March from Kiangsi. Still largely ignoring the Japanese aggressions, Chiang began to mass another army for a fresh attack on Mao and the Communists in ’36, but his own generals became so distressed at his lack of concern for the Chinese nation’s defense from the Japanese, they KIDNAPPED him and forced him to confront the Japanese while accepting aid from the Communists to fight a "common foe".

That was so contentious an alliance that by the end of 1940 the Nationalist Komintang launched attacks on the Communists instead of the Japanese! America wasn’t aiding either Chiang or Mao at this time, and war with Japan or not, that feud between the Nationalists and the Communists was to remain the central struggle in China until 1949. Weapons or no, supplies or no, training or no, advisors or no, the Chinese were too busy fighting each other to mount a concerted defense against the Imperial Japanese.

I put this together from old papers I had written for one of my Senior level courses back in 1993, and oddly enough I still had the thesis in the house. It wasn’t on this particularly, but related to it as it focused on the little known American Homer Lea, who was the hunchbacked dwarf, military advisor, and author who donated the royalties to Sun Yet-Sen from his first book so that Sun could finance his revolution. Look him up someday, interesting fellow Mr. Lea. His diagnosis of global power struggles and how they would play out is spooky. Valor of Ignorance is the most striking, Day of the Saxon is excellent, although unpublished the basis of Swarming of the Slav isn’t too bad either. Remember, Homer Lea died in 1912 two years before WW1 even started.

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Happy Trails,
Clint.