In the first place, there is context. Life in the China of the first half of the 20th century was cheap, as writer Lu Xun wrote after witnessing the nationalists clinically murder students in Shanghai in 1926. After the imperial throne fell on New Year's Day 1912, China imploded into territories dominated by warlords over whom the nationalist government never established proper dominion.
China was in economic stasis. The Confucian gentry - mandarin officials, landlords and merchants - had so effectively delivered the stability that hundreds of millions of peasants craved, that together they became an obstacle to vitally needed change. The peasants were wedded to obsolete farming techniques on tiny plots; the Confucian gentry were wedded to a system that allowed them to become absentee landlords for around half of China. They continued to run the country at the behest of the warlords, still genuflecting before Confucian maxims that were now hopelessly outdated. Japan's invasion in 1931 could not be effectively opposed.
There was a craving for a decisive rupture with all that had produced this. Radical egalitarianism, a kind of transformed Confucianism, seemed the only way to respond. The Confucian mandarinate had to be broken. The land had to be taken off absentee landlords. Savings had to be mobilised in a collective effort to create a modern industrial base. There seemed no other viable prospectus.
Mao gave vent to this ambition. The negative side of the Maoist balance sheet is well-known: mass murder, famine, injustice, and economic waste. But there are less well-known positives. Industrial output climbed 13-fold, albeit from a tiny base. The rail network doubled. Half of Chinese land became irrigated. There was a dramatic lowering of illiteracy. Near universal healthcare was established. Life expectancy rose; and despite Mao's appetite for imperial-style concubines, women were given the same right to petition for divorce and education as men. Their position was transformed.
And if Mao created an economy that while desperate for reform at least existed to be reformed - a statement that could not be made in the hyperinflation of 1949 when the Communists took over - he also bequeathed an ideological legacy that would permit reform. The Maoist communist concept of the so-called mass line meant that ideology and policy would emerge from respecting local differences and conditions. As a result, state planning and collectivisation of agriculture could be reversed more quickly in China than in the Soviet Union, under the guise of respecting local autonomy and creating local responsibility. Deng Xiaoping, the mastermind of the reform programme, was punctilious in describing the first phase of market-led reforms and decollectivisation in these Maoist terms.
Few western critics today appreciate the scale of the task confronting any moderniser of China in 1949. Western economies created the surpluses to finance industrialisation through incredible exploitation - of their own working class, and in the US via slavery. It was never likely that China could achieve self-sustaining economic growth without great collective pain to achieve its own surpluses, or that this could be done without the involvement of the state. Spontaneous market-led industrialisation is a myth.
This is certainly how Mao saw the task, with egalitarianism and collectivism the means. The German sociologist Max Weber, in a famous essay, argued that statesmen facing these kinds of challenges - of winning a war or of master-minding economic development - have to be judged by different moral criteria. Their decisions are means to achieve this ultimate end, and their choices have to be judged by this criteria rather than their inherent moral worth. Truman, for example, justified dropping the atom bomb on the Japanese because of the value of the ultimate end. Mao would justify his radical egalitarianism in the same way. We know that he was wrong. He, authentically and passionately, did not.
Yet that is insufficient excuse. The superiority of liberal democracy over communism is that when politicians take ultimate-end decisions they know they will have to justify them before a wide and critical audience - which means they must have very good arguments to justify them. Truman's nuking of Japan is still questioned, tribute to the vigour of democracy. Mao only had to justify his decision to himself, or arrest or kill his critics. Even today's Chinese communists recognise it is an inadequate framework.
The condemnation of Mao that convinces the majority of Chinese they need to change has to be more subtle than simply joining, say, Jung Chang and Jon Halliday in their book on Mao and seeing him as unrelievedly evil. Most Chinese are never likely to accept the verdict, not least because it is only a partial version of the truth. The better course is to build on Deng's description of Mao's Great Leap Forward and the Cultural Revolution as China's " treasure", because they proved that radical egalitarianism was wrong.
But the lesson Deng drew - that the party can remain in Leninist control of a market economy that needs no democratic institutions -was as wrong as Mao's. Today's China is in many ways going back. The healthcare that covered nearly all of rural China under Mao now covers just 5%. China spends less on education than other developing countries. Inequality is high. The country is sliding down international indices for good governance, corruption and business competitiveness. To return to Mao's solution to these issues would be wrong and immoral; but neither can China continue as it is. The best option is to embrace democratic institutions - and the path to doing that is not to repudiate Mao but to see him for what he was. Wrong and cruel, but part of China's groping to find a way to cross the river.
· Will Hutton's The Writing on the Wall is published this week at £20; to order a copy for £18 with free UK p&p go to theguardian.com/bookshop or call 0870 836 0875