Wang Dan remembers the emotions flowing through Tiananmen Square 30 years ago. It started with conviction, then drifted into confusion. There were bouts of anger and waves of joy … and then ultimately, deep despair.

"I have to admit that we were naive 30 years ago," he says. "We still had hope for the Chinese Communist Party. That's why we went to the street."

Indeed, Wang led the first cluster of students from Peking University to Tiananmen, the broad square in the middle of the city and at the centre of Chinese political power. Theirs was a spontaneous move, a walk in the dark that sparked a revolution.

It was spring 1989, and the students were mourning the death of Hu Yaobang, the former head of the Communist Party. His ideas for Western-style reform had inspired many young Chinese, but alarmed the old guard who had removed him from office two years earlier.

Wang was 20 years old, a freshman at the university. He had been a member of the Communist Youth League, but also an inspiring speaker on democracy. He says the students were looking to find a reason to hope.

"We were hoping for a better China, which means more democratic and more liberal policies," he says.

Wang Dan reflects on the 30th anniversary of the Tiananmen Square massacre:

Wang Dan, who led the first cluster of students Peking University to Tiananmen in 1989, recalls what happened in the square on the 30th anniversary of the crackdown. 1:00

"We wouldn't do it by ourselves, but we would push the government to do it. We just wanted the government to feel the pressure from the people."

Over seven weeks of sit-ins and hunger strikes in Tiananmen Square, the movement brought out not only students but factory workers, intellectuals and many ordinary Chinese. More than a million marched in the streets of Beijing, with smaller protests across the country.

How can we say that China did not handle the Tiananmen incident well? - Defence Minister Wei Fenghe

At times, it looked like the movement was on the verge of success, as reformers in the Chinese leadership negotiated with students and even seemed to sympathize.

"The student leaders never thought they would mobilize so many people. Several days [earlier], they were just students," says Wang Juntao. He was the head of China's first private think-tank on political reform and an adviser to the students.

"And now they were political leaders — and probably the most powerful leaders in the world at that moment."

This 1999 documentary looks at the protesters who led the charge:

A 1999 documentary looking look at Wang Dan and other protesters who led the charge against the Chinese Communist Party in 1989 12:29

In the end, though, sensing an existential threat to the Communist Party and its grip on China, hardliners won out.

Heavily armed troops moved on the square on the night of June 4, 1989. Under the orders of paramount leader Deng Xiaoping — and under the gaze of Mao Zedong's portrait — they shot hundreds of protesters, likely more than 2,000 in all. The exact number of victims of the Tiananmen Square massacre has never been known.

A wider view of the demonstration at Victoria Park in Hong Kong shows some of the thousands of people who attend a candlelight vigil honouring 1989s protesters in Tiananmen Square. (Saša Petricic/CBC)

One protester famously stopped a row of tanks by blocking the path and refusing to move. Another protester, speaking to a Tiananmen conference in Taipei recently, described how a tank "ran over my body" and paralyzed his legs for life.

Wang Dan, at the top of the regime's most wanted list, was sentenced to four years in jail. Wang Juntao was accused of being a "black hand" behind the protests and received a sentence of 13 years in prison. Both men now live in the U.S. and are barred from returning to China. They were interviewed by CBC News in Taipei.

The massacre, officially known as "the June fourth incident," quickly became a taboo subject in China.

Scrubbed from history

Many of today's students know nothing about it. They are told "never ask" by teachers and parents, according to several young people who spoke to CBC but were too afraid to have their names used.

The entire episode has been scrubbed from history books, barred from any classroom discussion and ignored at the National Museum of China that faces Tiananmen Square. Try discussing it on China's closed internet and all mention will be censored, text messages are erased before your eyes.

In the leadup to today's politically sensitive anniversary, China's security services have been detaining and interrogating former student leaders, human rights activists and anyone else who might speak out.

A group of Hong Kong University students clean the 'The Pillar of Shame', an art piece dedicated to the victims of the 1989 Beijing Tiananmen Square massacre, at Hong Kong University on Tuesday. The pillar was created by Danish artist Jens Galschiot in 1996. (Jerome Favre/EPA-EFE)

More than 20 members of Peking University's Marxist Society, student activists who criticize the government for straying from communist ideology, have either been placed under house arrest or have disappeared into police custody.

Beijing doesn't normally acknowledge anything about the crackdown in public, but in a rare comment this weekend, China's minister of defence said it was the "correct" move.

'Needed to quell'

"How can we say that China did not handle the Tiananmen incident well?" said Wei Fenghe at a security forum in Singapore.

"That was a political turmoil that the central government needed to quell. The government was decisive in stopping the turbulence," he said. "Due to that, China has enjoyed stability and development."

Visitors crowd into the Tiananmen protest museum in Hong Kong to watch videos and remember student movement and crackdown 30 years after it began in Beijing. (Saša Petricic/CBC)

In fact, that was the unspoken deal in the years after the protests and the killings, one that changed China.

China would offer its citizens unprecedented income growth and prosperity through economic reforms, but few political freedoms. The party was not to be challenged.

People's hopes were shattered, and there was a wave of emigration to other places. - Teresa Wong, a child at the time

Per capita income has grown to $8,827 US in 2017 from $310 in 1989, the latest World Bank figures, creating an enormous middle class. And according to Forbes magazine, China now has 324 billionaires, more than any other country except the United States.

At the same time, room for individual freedom and dissent has shrunk dramatically, especially in the current era of Chinese President Xi Jinping.

Ideological correctness and education has been imposed on students and professors, many of whom are barred from speaking with foreign media. An entire region of China, Xinjiang, faces an unprecedented religious crackdown that has seen millions of Uighurs locked up and many mosques destroyed.

And Hong Kong is feeling the pressure from Beijing.

It is the only part of China that retains significant freedom of speech, and the only place where the 30th anniversary of the Tiananmen massacre will be publicly remembered in a candlelit vigil.

The small Tiananmen museum, showing videos and displaying T-shirts and banners was crowded this week.

Teresa Wong remembers as a young child her parents watching the protests and the crackdown, horrified. Her family left Hong Kong for Germany shortly after.

"That was one of the triggers," she says. "People's hopes were shattered, and there was a wave of emigration to other places."

Those who live in Hong Kong now say that as China continues to flex its muscles and limit freedoms in the former British colony, they may have to bring back mass street protests of the 2014 "umbrella movement," and even intensify them.

"The situation in Hong Kong is getting worse," says Eric Ching. "The only way is to take radical action, to prevent HK people from being in same situation as people in the mainland."

Wang Juntao says the discontent will spill over in China as well.

"I believe the large-scale protests will happen in Tiananmen Square again," he says. And this time, he predicts, "it will overthrow and end Communist Party rule."