Chinese Communist leaders had long seen the war as inevitable because their experience and their ideology convinced them that Japanese expansion in China was fuelled by irreversible forces. ‘The main characteristic of the present situation,’ the CCP reiterated as a litany, ‘is that Japanese imperialism wants to turn China into a colony.’ The CCP also saw the war as necessary and, after the end of 1935, called for unified resistance at the earliest possible moment. Mao and his followers knew that in a Sino-Japanese war they could claim, as patriots, a legitimate, honourable, and self-defined role. Indeed, they intended to claim a leading role in moral terms. For them the only alternative would be a Sino-Japanese peace from which they would surely be excluded and which might be purchased at their expense. Every delay in resistance bought time which the KMT might use to continue campaigns against the CCP. Every delay prolonged the period in which Tokyo and Nanking might come to some further accommodation, possibly including joint anti-Communist action, as Japanese Foreign Minister Hirota had proposed in August 1936.

One need not impugn the CCP's sincerity to note that termination of civil war, a broad united front and resistance to Japan would also serve the party's interest. Its platform matched the mood of urban China – of students, intellectuals, large sections of the bourgeoisie, and many workers – far better than the Kuomintang's repressive call for ‘unification before resistance’.

This book fills a special need. The two decades of Nationalist rule on the mainland (1927–1949) were among the most critical in recent Chinese history. During those years, the Nationalist Party, led by Chiang Kai-shek, endeavored to consolidate its revolutionary victory of 1927–1928 and to build a nation based on Sun Yat-sen's Three Principles of the People. At the same time, the revolutionary party led by Mao Tse-tung, drawing inspiration from the principles of Marx and Lenin, grew from a seemingly insignificant guerrilla band in the rural hinterland of Kiangsi Province into a military and political force that shook not only China but the world.

Yet none of the existing college textbooks on modern China presents the events of this momentous period comprehensively or on the basis of the most recent scholarly literature. Until the 1970s, most of what Westerners knew about the Nationalist period was gleaned from such journalistic accounts as Edgar Snow's Red star over China, Theodore White and Annalee Jacoby's Thunder out of China, and Jack Belden's China shakes the world – wonderful books that can still be read with excitement and benefit. In recent years, however, academic historians have been turning their attention to these critical decades. As a result, a spate of books, articles, and doctoral dissertations have substantially modified our understanding of the Nationalist period, shedding new light on the character of Nationalist rule and on the sources of the Communists' revolutionary victory.