The question of whether the Communist Party of China (CPC) would have had a chance to win the Chinese Civil War if Japan had not invaded China is a complex one and subject to speculation. It's important to note that historical events are influenced by numerous factors, and changing one factor can have a ripple effect on the entire course of history.
However, it is widely believed by historians that the Japanese invasion of China, which began in 1937 and lasted until the end of World War II in 1945, played a significant role in shaping the outcome of the Chinese Civil War. The invasion placed enormous strain on the ruling Kuomintang (KMT) government, led by Chiang Kai-shek, as they were forced to divert resources and attention to fighting the Japanese.
The CPC, led by Mao Zedong, took advantage of the chaos caused by the Japanese invasion to expand its influence and gain popular support among the Chinese population. The CPC was able to portray itself as a united front against the Japanese aggressors and positioned itself as a force fighting for Chinese independence and liberation from foreign occupation. This helped the CPC gain credibility and support among the Chinese people, which proved crucial in their eventual victory in the civil war.
If Japan had not invaded China, the dynamics of the Chinese Civil War would have been different. Without the external threat posed by Japan, the KMT might have been able to focus more on suppressing the CPC and maintaining control over the country. The KMT government had significant military and financial resources, and without the drain caused by the war against Japan, they may have had a better chance of effectively countering the CPC.
That being said, it is important to recognize that the CPC had gained significant support and legitimacy even before the Japanese invasion due to various factors such as their land reforms, grassroots organizing, and guerrilla warfare tactics. The CPC had successfully established base areas in rural China, which served as strongholds for their operations.
In summary, while the absence of a Japanese invasion might have altered the conditions of the Chinese Civil War, it is difficult to say with certainty whether the CPC would have still emerged victorious. The war was a complex and multifaceted conflict, influenced by a range of factors, and any alternative scenario would involve a degree of speculation.