Comment Central: 5 other momentous anniversaries to mark

June 4, 1989, was a vicious day in China’s history. It was by no means the most brutal episode in the Communist Party’s rule: the Great Leap Forward claimed millions more lives, the Cultural Revolution meted out cruelty for years. But Tiananmen marked a murderous, horrific exercise of state power. In at least partial view of a watching world, it was also the high-water mark of that power, the zenith of the Communist Party’s monopoly. It was also the moment when Deng Xiaoping, the veteran party leader, had to choose: to reassert, by force, Communist Party rule, or to co-opt the forces of democracy and risk seeing the gradual dilution of power of the organisation that had dominated Chinese life for the past 40 years.

He chose force. And in doing so, he destroyed for millions of admirers in the West his reputation as a reformer and a man who would lead his country towards the freedoms that were quickly spreading throughout Eastern Europe. But Deng, like others who had resorted to force to perpetuate communist rule, knew that the only way to win back respect from his own people was to show that he had acted to protect their interests. That meant delivering prosperity. And to do that, he embraced economic liberalisation with an extraordinary energy and commitment. It was a bold decision for an old man at the end of his career. And it is one that, 20 years later, most Chinese believe has brought huge rewards.

Deng’s legacy has gone way beyond the “goulash communism” of Janos Kadar, the Hungarian leader who rode to power on the back of Soviet tanks. Today China’s citizens have economic choices unimaginable to them a generation ago: what job they can do, where they can live, what they can watch on television, which mobile phone company they can select. They have economic liberty. But, as plain-clothes police patrol Tiananmen Square, internet websites are taken offline and anyone who was witness to the events of 20 years ago is “invited” to move for a spell to the countryside, it is clear that the lack of freedom and democracy still weigh on China.

Times Archive, 1989: Bravery, hatred and ongoing carnage

At noon yesterday, when tanks started moving along the Changan Avenue, I watched as a man in a white shirt ran from a crowd

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• Message from the square

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This lack of freedom stunts any real debate on the future of China. Thinking is still circumscribed. There are areas that are still taboo or where intellectuals can only hint at what they mean. In three vital spheres, this is deeply damaging to China’s national interest. The first is foreign policy. China has evolved in less than a generation into a world power, one now placed alongside America in a newly minted category of G2. But the country is uncertain how to exercise this power. And as long as the party restricts the debate to a known ideological framework, it cannot mobilise China’s vast intellectual capabilities to address this. The second area, intellectual property, is equally damaged. As long as there is no real freedom to question the foundations of society, China will not produce innovators. It will be able to copy and develop, but not to outstrip competitors and set the framework for the world. And the third area is the legitimate assertion of religious and regional identities alongside Chinese citizenship.

Twenty years on, there is an irony. In 1989, the students were surrounded by the forces of the State. Today it is the party members, secluded in their Beijing headquarters beside the Forbidden City, who are surrounded by the people.