Tiananmen Square, 1989 Photo: Jeff Widener/AP

For some, the events that occurred in Beijing 19 years ago today have been pushed towards the sidelines of history.

The Great Leap Forward and the consequent famine or the 10 years of the Cultural Revolution were, in purely quantitative terms, much longer and bigger (including in terms of victims) that the massacre of protesters on the night of June 3-4 1989.

Besides the economic expansion of the last decades, the Beijing Spring can all too easily take on the aura of a carnival which ended in tragedy and, basically, led nowhere. Ken Livingstone compared it to the poll tax riot in London, and "friends" of China take care to describe it as the Tiananmen Incident or, at most, as a "clampdown". The protesters have been suppressed or forced into exile across the globe, except for those who have come to terms with the regime that rules in the new China; a few are still in prison.

What happened that night is a non-event as far as the rulers of China are concerned; commemoration is suppressed and, if it is remembered at all, the occasion is portrayed as a glorious defence of the people's true interests by the army. How many people died remains unknown, though what is clear is that most were not students in Tiananmen, but ordinary citizens of the capital trying to stop the armoured vehicles after previous successes at blocking their progress to the square.

Yet June 4 remains a crucial moment in China's history, as I have sought to show in a new history of China that seeks to link past and present. The killings of June 4 were enough of a tragedy in themselves. But, beyond the deaths along the boulevard leading to Tiananmen and then in the square, the outcome of the Beijing Spring confirmed China in a political course which reaches back into distant history, but from which, crucially, Deng Xiaoping and his elderly colleagues decided not to divert 19 years ago.

The patriarch, the ultimate survivor of the Communist system, embarked on the path of economic, market-led reform in 1978 after his victory over Mao's anointed successor, Hua Guofeng. While this was hugely successful in one sense, kick-starting the moribund economy and bringing China into the world economic system, it had, by 1989, aroused widespread resentment bred from the inequality Deng saw as necessary for growth, inflation and corruption.

But there was a more fundamental question: if the Chinese were to be free to run their lives economically, why not politically as well? If the command economy was being dismantled, why not the command political system, too?

The student demonstrators in the square may have lacked a coherent message. The atmosphere may have taken on aspects of a carnival. But, underlying it all, was a basic questioning of the right of the Communist Party to exercise monopoly power, a demand for discussion and plurality.

That questioned a tenet of Chinese rule dating back to the First Emperor of 221BC. The doctrine of legalism - rule by law rather than rule of law - co-existed with the more benevolent strains of Confucianism. Mao had identified himself with the First Emperor, and in 1980, Deng and his colleagues were in no mood to cede the authority they had spent all their lives fighting for.

Their decision to declare martial law and send in the People's Liberation Army was not taken lightly. As shown in the smuggled-out records in the book, the Tiananmen Papers, they deliberated long and hard, often in deep disgruntlement as they discussed how to deal with the pesky students who could draw on the traditional esteem in which their class was held in China. Reformists in the leadership, led by the party secretary, Zhao Ziyang, tried to find an accommodation. By the beginning of June, some student leaders were ready to return to campus and build on the moral victory they had won since launching the protest in mid-April. But the moderates were overruled on both sides and the tragic result unfolded.

That may say something about the dynamics of a student movement that was poorly co-ordinated and lacked clear, realisable aims - and was filled with its fair share of egos and hotheads. But it says a lot more about the Chinese leadership, then and since. The desire for compromise, for understanding, for a peaceful way forward that encompasses as many participants as possible has little or no place in a tradition that, stretching back through the imperial millennia, puts a premium on top-down rule with force always lurking in the background to be used on dissidents who are portrayed as traitors to the received wisdom exercised by the rulers. Against that, the moderates, were they Zhao or the student leader Wang Dan, could not make reason prevail.

Gathered in Deng's house as they circumvented the constitution and Zhao Ziyang to impose their will, the elders convinced themselves that the students must be manipulated by foreign enemies and "black hands" operating clandestinely in Beijing - some of those who tried to mediate a settlement found themselves cast into that category and sentenced to long prison terms. The Mandate of Heaven, in the form of Communist rule, was sacrosanct. No brick could be removed form the edifice for fear of brining it all tumbling down.

As protest spread to more than 100 cities and the citizens and workers of Beijing rallied in support, the reaction was not to question where the regime might be going wrong, but for the leaders - with the exception of Zhao and his adviser, Bao Tong - to dig in their feet. When the people of Beijing peacefully stopped the tanks on their first sorties into the city, the consternation in the leadership compound was palpable. So the hardliners triumphed; martial law was declared; Zhao was ousted; and, on the night of June 3, the tanks did not allow themselves to be stopped on their way to the square.

That reaction from the top and the regime's inability to handle protest peacefully made June 4 1989, a crucial moment in China's modern history. Deng could have taken a different decision, to seek a reasonable way forward, admitting criticism and debate to try to solidify a regime which needed to grapple with the wider issues raised by the economic reform he had unleashed. It would have been difficult and messy, but it was not out of the question, and would have given him a unique place in history.

By putting the primacy of monopoly power first, the aged patriarch closed off a key avenue of potential progress for China and, once he had re-launched his drive for the market in 1992, gambled all on material progress being sufficient to give the Communist party popular legitimacy. That has made the people of China far better off, if in a highly unequal manner, and transformed the isolated Maoist state into a global player. A "China model" has emerged. People are, individually, far freer than they were under Mao, so long as they are not seen to represent any political threat to the regime. There is much lively debate in thinktanks and among intellectuals about whether to head right or left economically.

But it all remains cast in the one-party mode. The "Beijing Coma" cocoon imposed in 1989 remains in place. That provides the essential context for the burgeoning superpower, and has set China on a path by which it thinks it can defy western nostrums and pursue its own path. That is why June 4 1989 has to be remembered, not only to honour the dead, but also to understand the rising global power.