Here's a way to think about contradiction. There are progressive forces and reactionary forces. The CPC formed a united front with the KMT to break the grip the western powers held over China and end the century of humiliation. After this was done, the material conditions of China changed. Once the Chinese people had reclaimed their sovereignty from western colonialism, from Capital, they had a choice. Follow the still progressive CPC or follow the now reactionary KMT. The former representing the highest most advanced level of anti-imperialism and relations of production. With the latter, the KMT, representing a similar path to what Japan and South Korea took. Taking a junior partner roll as capitalist powers underneath the West-led Capital world-firm.
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