What social problem would be solved by a GuoMinDang attack on Shanghai in 1927?

Question

Professor Schwiedrzik's script (distribution limited to Viennese university students), elaborates that during the northern expedition two factions formed within the GuoMinDang in 1927. The left one was influenced by Borodin, the Russian adviser. It wanted to attack Beijing early on. The right one, Chiang Kaishek and his supporters, wanted to take Shanghai first.

The script repeatedly states the right group wanted to solve the "social problem" first, while the left group wanted to achieve national unification by sacking the capital.

I have searched my textbook and tried hard to find resources online, but I have no idea what "social problem" was to be remedied by taking Shanghai. I am hoping for your support.

In the accounts that I am familiar with, a split between left and right is pictured after the incident/massacre at Shanghai. But this script mentions a split even before and a "social problem" I can't find anything about.

Furthermore, it doesn't appear like social problems were Chiangs main concern at all. As far as I gather, he was greatly aided in taking Shanghai by a communist uprising. But as soon as the city was taken he started a purge of the communists and allied with those who thought their demands were extreme!

Answer 1

The "social problem" was the Communist influence in China, and ultimately the right-left split in the GMD. The reason that Shanghai was important was because the Communists were heavily concentrated in the city. So there were two GMD "attacks" on the city; the first, against the warlords that held the city, and the second, against the Communists and their allies, the labor unions. The Shanghai incident essentially wiped out the urban Communists, and only Mao tse-tung's peasant orientation allowed a revival.

This forced the left wing of the GMD to abandon their support of the Communists, and (temporarily) re-united the GMD. An attack on Beijing first would have represented a continued attack on the warlords, that would have left the issues of Communist involvement in the northern expedition and the GMD's left-right split unresolved.

As for Chiang's allies, they were the Chinese "Mob" and their leader was Chiang's personal friend (the two had been "drinking buddies in their late twenties and early thirties). They wanted to get control of the labor unions, and Chiang wanted to eliminate Communist control over them.

To paraphrase Chiang himself (in a slightly different context), "The warlords are a disease of the skin, the Communists are a disease of the heart," the latter being the "social issue" Chiang cared most about.