Thirty years ago in the spring of 1989, as the world’s most populous country teetered on the edge of freedom, I received a late-night phone call in my apartment in Beijing: The Chinese Army was invading its own capital.

Students and workers had made roads impassable by setting up barricades to block the army, so I jumped on my bicycle and pedaled furiously toward the gunfire. I reached Tiananmen Square shortly before the army, and then I watched as soldiers fired their automatic weapons directly at the crowd that I was in.

I was then the Beijing bureau chief of The Times, and I ran around that evening, the notebook clutched in my hand stained with the sweat of fear, to document horrors that remain seared into my memory. You never forget watching young people, some of the nation’s best and brightest, full of passion and idealism, stand up to machine guns — and then in an instant crumple bloody and lifeless on the ground.

Until that evening, millions of Chinese had marched freely for seven weeks in hundreds of cities across the country, denouncing corruption and seeking greater democracy. Sculptors had created a huge “Goddess of Democracy,” a Chinese version of the Statue of Liberty. Hope filled the air.