WHEN the second world war ended, the 3.7m-strong army of China’s leader, Generalissimo Chiang Kai-shek, was badly weakened by its fight with the Japanese and a Communist insurgency. But it still had the upper hand against the Communists: superior by far in numbers and equipment. As Soviet forces withdrew from Manchuria in the north-east, which they had taken from the Japanese, Chiang’s forces surged forward to regain the territory. Chinese Communists in the area, who had hitherto been backed by the Russians, were shattered by the onslaught.

But in 1946 the Americans, anxious to prevent an all-out civil war between Chiang and the Communists’ leader, Mao Zedong, persuaded Chiang to stop fighting. It was a moment that may have changed history: the few weeks’ hiatus enabled Mao to replenish his forces with Soviet aid. When the truce broke down, Chiang lost Manchuria and eventually the civil war. Americans—particularly right-wingers—kicked themselves about it for many years afterwards. What if Mao’s victory had been avoided?

China’s spectacular rise in the past three decades has helped the Communists parry suggestions that the country would have been better off without Mao. But it may well have been. Chiang’s army fled to the island of Taiwan, which prospered. Mao’s China suffered economic ruin before Deng Xiaoping eventually began to turn its fortunes around in the late 1970s. Had China’s economy grown at the same pace as Taiwan’s since 1950, its GDP would have been 42% bigger by 2010 than it actually was. In other words, it might have achieved its growth miracle plus another one about the size of France’s economy.

Chiang would have remained in charge of a corrupt, autocratic government with a brutal secret police. His Nationalist Party, the Kuomintang (KMT), would have faced discontent among the rural poor who formed the bulwark of Mao’s forces. However, Chiang’s brand of authoritarianism may have proved a softer one than Mao’s. There would have been no killings of millions of landlords purely on ideological grounds, and no Great Leap Forward in the late 1950s, which caused a famine that killed tens of millions. Unlike Mao, he would not have wiped out private enterprise and forced peasants to surrender their land to “People’s Communes”, a policy that exacerbated the famine and that—though long since officially repudiated—still plagues the development of China’s countryside. Neither would Chiang have plunged China into the chaos of the Cultural Revolution of the 1960s and 70s, during which millions more were killed or persecuted.

Under Chiang, China would not have had to wait 30 years before becoming part of the global economy. To be sure, Chiang would have tried to protect China’s markets from foreign competition, just as Taiwan and other Asian economies did during their periods of rapid take-off. But he would have been quicker to relax such restrictions. Taiwan was ready for membership of the World Trade Organisation long before China joined in 2001.

The strategic map of Asia would have been very different had Chiang won the civil war. He would not have supported North Korea’s invasion of the South in 1950. Without China’s backing, Kim Il Sung would probably not have got Stalin’s support for such a venture either. Chiang would not have had a Taiwan problem: Mao’s rebels never had a foothold there.

But Chiang was an ardent nationalist. His relationship with Japan would have been fraught. Millions of Chinese had been killed during Japan’s occupation of China, with the KMT rather than Mao’s forces suffering by far the worst casualties. Animosities between China and Japan, which Mao did not appear eager to play up, might have bedevilled east Asian security long before they did emerge in the 1990s as a source of regional tension. Chiang’s domination of Taiwan as well as the mainland would have given him control over the shipping lanes on which the economy of Japan depends. America’s restraining hand in the region may still have been needed.

The cold war might have turned hotter too. Chiang did not accept the Soviet Union’s control of Mongolia. Under Mao, brief battles broke out on the Chinese-Soviet border in the 1960s. They might have turned bigger and bloodier under Chiang. The Chinese public, indoctrinated by the KMT into a belief that Mongolia was China’s, might have clamoured for their government to assert the claim more forcefully once the Soviet threat was gone.

But China by then may have become a more politically liberal country. Moves towards democracy would have been slowed by fears of secessionism, especially in Tibet and other ethnic-minority regions (many Taiwanese would have been chafing at the KMT’s rule; they had begun to even before Chiang fled to the island). But a middle class would have grown far sooner than it has under the Communists.

Despite the autocratic rule of Chiang’s KMT, China would have remained an ally of America. Asia would therefore not be riven as it is today by a struggle for supremacy between America and China. Perhaps even Japan would be learning to live with its powerful, rich neighbour.

Much of the tension that now plagues Asia relates to the nature of China’s Communist Party. Neighbouring countries worry about the way the party behaves: secretively, high-handedly and sometimes (at home at any rate) brutally. But all of them fear what might happen were the party now to follow the KMT’s path and liberalise. The KMT was voted out of power in Taiwan in 2000, before returning in 2008. It is likely to be voted out again next year. Few in Asia believe that the Communist Party could ever accept the vagaries of democratic politics. Its eventual demise might well involve bloody tumult; a return, even, to the chaos of the 1940s. The rest of Asia would prefer the devil it knows.