During the student protests in Tiananmen Square 10 years ago, Chinese demonstrators smiled and waved at foreigners, seeing them as their allies in their struggle against the Communist government. This weekend, as angry students poured into the streets of Beijing for the first time since 1989, the attitude to Westerners was very different.
Outraged by the NATO bombing of the Chinese embassy in Belgrade which killed four people, students and teachers converged on the narrow poplar-lined avenues around the US embassy with banners and flags, shouting slogans against foreigners.
They glared at non-Chinese people, sometimes stopping them to ask "Where are you from?" and "Is your country in NATO?" The anger against NATO, and the Americans and British especially, expressed itself physically on a few occasions when foreigners were jostled on the street.
The Chinese government called the bombing "a barbarian act" conjuring up historic images of foreigners as barbarians intent on humiliating China. The official Communist Party newspaper, the People's Daily, added to the hysteria by accusing NATO of "deliberately spilling Chinese blood".
Several reporters were roughed up as the day went on and anger grew at what people saw as a intentional infringement of Chinese sovereignty. A French cameraman was forced to retreat under a shower of stones. CNN's bureau chief, Rebecca MacKinnon, had her glasses knocked off by an incensed man as she tried to conduct an interview.
Many correspondents from NATO countries escaped from angry groups by claiming to be Irish or Swedish. Among the furious crowds were students from 10 Beijing universities, supplemented by artists, writers, workers and journalists. They carried a sea of banners and placards with such slogans as "Revenge", "Clinton is Hitler", "Smash America", "Fuck NATO" (a favourite), "NATO Nazis", "Teeth to teeth, eye to eye" and "Blood for blood". No one believed the Belgrade bombing was an accident. A student from the Poly technical Institute said: "NATO is going crazy like the Japanese went crazy in the war and did bad things." The key aspect of the weekend demonstration was the way the government controlled events.
The protests began spontaneously in the university campuses on Saturday afternoon as the news from Yugoslavia unleashed an anti-American fury which has been simmering over an accumulation of grievances from the snubbing of China in the United Nations to American allegations of Chinese theft of nuclear secrets.
College authorities reached a compromise with the students. They promised to provide buses, banners, flags, placards and megaphones and bring them to the embassy area in east Beijing, so long as the students returned to the campus when asked.
Uniformed police closed down the bustling silk market beside the US embassy gates before the first fleet of buses arrived at 4 p.m. Signs were put up saying "Protest Route" and lines of unarmed police channelled the crowds, first past the British embassy and the British ambassador's residence, and then the American embassy a few hundred yards away.
The demonstrators broke paving slabs and threw volley after volley of rocks, plastic bottles, eggs, paint bags and even old shoes at the embassy buildings, under the benign eyes of rows of police. This continued all through the night and again yesterday, until every window was broken, the walls covered with paint stains and the light globes on the entrance pillars smashed.
Opposite the British embassy a huge crowd spent hours on the walls and trees of the Albanian legation, which was also stoned. Among them a cheer-leader sounded a gong to celebrate every time a window was hit.
A reporter asked a guard at the US embassy gate as a barrage of stones soared into the air: "Why don't you stop it?" He replied: "Why should we? They bombed our embassy." When police pushed back students who tried to set fire to the US consular building they were greeted with shouts of "Traitor!"
A silver-haired university professor took me aside in the tumult to say with venom: "I've come here to protest about the American shits." A student pushed a leaflet in English into my hand. Full of obscenities, it read in part: "Bill Clinton, you traitor to your family, traitor to your people, now you make us bleeding, bastard is your name."
Throughout the warm, still hours of darkness on Saturday evening and again last night foreign residents in the diplomatic compounds were kept awake with chants from the ever-moving throng of "Down with NATO!" and "Advance! Advance!" from the Chinese national anthem.
With the diplomatic compound in turmoil, Foreign Ministry officials telephoned ambassadors to tell them not to leave their cars in the streets. Four black American cars with their distinctive 224 registration plates were smashed.
Inside the US embassy an emergency action committee met to consider the deteriorating situation. The consular building nearby was abandoned as staff retreated to a secure room in the embassy.
Americans in Beijing were advised individually to stay indoors except to buy food. Parents whose children attend international schools in Beijing were told through pyramid "phone trees" yesterday that the schools would not open today or tomorrow.
The sudden return of turmoil to the streets of Beijing comes at a most sensitive time in Chinese politics, just three weeks before the 10th anniversary of Tiananmen Square on June 4th. I asked a student leader from Peking University how he defined the difference between then and now.
"In 1989 the students were against the government," he said. "Now we are for the government." Nevertheless the sudden licence to demonstrate, and the state-sanctioned stone-throwing, have injected an element of volatility into China, where there has been growing unrest among laid-off workers and two weeks ago a large demonstration by Falun Gong believers which caught the government off guard.
Playing the patriot game by appeasing outraged nationalism helps legitimise a government fast losing its ideological grip on its people, said a senior diplomat. Chinese history shows, however, that pro-government demonstrations can quickly become a vehicle for other frustrations.
The May 4th movement 1919 erupted when students rioted in protest against the weakness of the government in dealing with foreign powers. In 1976 the death of the prime minister, Zhou Enlai, was used by students as a pretext to unseat the Gang of Four.
The pro-democracy demonstrations in 1989 began on April 15th when the former general secretary of the Communist Party, Hu Yaobang, died and university campuses spontaneously blossomed with banners and wall posters eulogising the disgraced reformer.
"The mood could also change this time," a lecturer conceded, "but it's unlikely and only if the government does not take a tough line with NATO."
"The only thing that will calm this crowd," said a Chinese consultant, "is if Clinton comes on television in person and apologises in Chinese." Perhaps the most worrying comment for President Jiang Zemin, who recently promised an end to China's humiliations, was a remark from one middle-aged man: "If Mao was alive this would never have happened."
Ironically the bombing of the Chinese embassy came just as Beijing was toning down its criticism of NATO for the air campaign against Yugoslavia. The Chinese government and media had furiously denounced NATO when it began bombing seven weeks ago, but the policy had begun to undergo a subtle change.
Li Peng, the second-ranking Chinese leader, visited Turkey, Syria, Bangladesh and Pakistan - all Muslim countries - in April and found that the Islamic world was not happy with Beijing's unquestioning support for President Slobodan Milosevic. Chinese leaders in recent days had begun to allow previously-suppressed reports of the ethnic cleansing of Muslim Kosovans to appear in the official media.
At the same time Beijing had become desperately concerned at the prospect of instability in Tibet and Xinjaing province which have large ethnic populations. With deep-seated fears about possible US intervention in China amid similar chaos in these two regions, the Communist Party had reportedly set up two high-level committees to study policy options.
The Chinese public security bureau had advised universities not to invite Yugoslavian diplomats to give talks to students. Following Thursday's Group of Eight nations agreement in Bonn on Kosovo, securing China's acquiescence had been the next priority for the West before putting a resolution to the UN Security Council.
All that has been put on hold now as Beijing students vent their anger on the Beijing streets, with profound and still uncertain consequences for the future of China itself.