Memory is a powerful repository of images, symbols and emotions that suffuse present and future human action. Remembered past, especially of public events, has a tenacious hold over the mind and can make people move mountains. Knowing the potential of history to stir mass sentiments, ruling elites across the world try to enshrine, rewrite or erase it as per their interests.

Authoritarian rulers are the most zealous gatekeepers because their political systems? past is traumatic and could light prairie fires of unrest.

For the Chinese communist party to even acknowledge that, exactly 20 years ago, it ordered a massacre of epic proportions (killing upto 7,000 protesting students and workers) in Beijing?s Tiananmen Square and around the country would open floodgates to demands for apology and regime change. So, the same state that declared a public holiday to celebrate ?Serf Emancipation Day? on the 50th anniversary of its invasion and occupation of Tibet in March is in denial for capital crimes committed in the heart of the country.

Not taking chances in the lead-up to the Tiananmen anniversary, the party ordered a crackdown on dissidents planning to carry out processions to honour the dead and renew calls for ending dictatorship. Anticipating likely channels for mass discontent, state agents shut down popular Internet forums, banned students from giving interviews to foreign media, and scheduled countrywide university exams on June 4 to keep the young off the streets.

The Chinese state?s capacity to normalise repression and maintain ?harmony? is so notorious that only in the libertarian air of Hong Kong are large popular demonstrations likely on the anniversary. In the communist party?s version, only 241 were killed that day, some of whom it claims were soldiers. Its line of reasoning is: ?Why all the fuss? Let us move on and celebrate the glorious achievements of the People?s Republic since that day, where we have reduced absolute poverty and made the country a great economic and military power.?

The problem with citing economic performance as an alibi for covering up crimes against people is the assumption that filled bellies are contented souls. If rising prosperity and stupendous economic growth were enough to legitimise the communist party?s rule, why would the entire state security and intelligence apparatus have to be pressed in to sanitise Tiananmen Square in advance of the anniversary? The state?s propaganda that foreign saboteurs could instigate trouble on June 4 is an insult to the will of the Chinese people to live in a more open society.

Since 1989, the state?s education system has tried to brainwash the younger generation to consign the memory of Tiananmen to a footnote. When movie icon Jackie Chan recently commented that ?we Chinese need to be controlled? since a free society is not suitable to their natures, he echoed the myths being drilled in the mainland.

A firestorm of criticism against Chan?s remarks erupted, but only in Hong Kong and Taiwan.

In George Orwell?s 1984, a Ministry of Truth operates an elaborate machinery of mind control to keep the masses pacified with the slogan ?Ignorance is Strength?. The Chinese communist party tries this but is not completely successful. Hence the need to clamp down, arrest, witch-hunt and smother voices asking for an accounting of the horrors of the past.

Tiananmen is a blip compared to an even bloodier episode in Chinese history whose anniversary also falls in 2009. The famine of 1959 following Chairman Mao?s forced collectivisation drive killed some 30 million Chinese. A Chinese state ever ready to rant against Japan for crimes committed prior to and during World War II is deafeningly silent about its own revolutionary terror.

Political scientist Minxin Pei argues that China?s ?developmental autocracy? consistently fails to provide accountable government and fully release the economic energies of its people. When economic miracles are obtained at terrible human cost, pressure builds up for a backlash. It is to guard against such a reaction that the Chinese state is falsifying history and choosing which anniversary to remember and which to forget.

June 4 is a tragic reminder of the undeclared state of war between the Chinese communist party and its own people. It is history?s wound that cannot be left untended forever.

?The author is associate professor of world politics at the Jindal Global Law School