When I was a boy, I liked to argue with adults about history. I’d ask questions that are impossible to answer, like whether the United States would have become a superpower if the South had won the Civil War, or whether we’d all be speaking a different language if the Allied forces hadn’t defeated Adolf Hitler’s Nazi Germany.

I formed my own opinions too, mostly based on facts I learned at school. One of the more heated debates I had was with my grandfather, a Korean War veteran. I told him I thought the U.S. was wrong to drop atomic bombs on Japan during World War II.

He said the bombing was necessary to end the war, and that I didn’t understand how brutal the Japanese soldiers were. But what about all the innocent people in Nagasaki and Hiroshima killed by the bombs, I asked. What did they do to deserve to die?

It was the only way to end the war, he repeated.

He was right about at least one thing: I didn’t understand how horrible Japanese soldiers had treated prisoners of war and civilians. It wasn’t covered in great detail by my history professors and rarely mentioned outside the classroom. That’s not the case in China, where I live now. Sixty-seven years have passed since the war ended, but the animosity among the Chinese toward Japan for atrocities committed during that period is still very alive.

A few days after the March 2011 earthquake and tsunami in Japan, I watched a news report on China’s CCTV about the disaster. A reporter was talking to random passers-by about the massive loss of life. One of the people interviewed, an elderly man, said he felt sorry for the people who died, but that Japan had it coming because of the way they treated the Chinese in Nanjing during the Second Sino-Japanese War (1937-1945).

Nanjing is located in southeastern China’s Jiangsu province along the Yangtze River. Its name means “southern capital” (Nanjing was the capital of China for 53 years during the Ming Dynasty).

The city was one of several major Chinese territories captured by Japan during the war. But it stands out because of the estimated 300,000 Chinese who were massacred by Japanese soldiers from 1937 to 1938. The slaughter is depicted in graphic detail through photos at the Nanjing Massacre Memorial Hall.

The museum was built in 1985 at the site of a mass grave. Some of the skeletal remains from the grave have been unearthed, and are now part of a permanent exhibition. Many of the skulls have slits and cracks from bayonet and gunshot wounds.

Images of the brutality are repeated throughout the museum in photos of gruesome executions and dead bodies. There are also video and written testimonies from survivors of the massacre. A few have been posted on the museum’s website.

“My father and second elder brother were killed by the Japanese army with bayonets at the door of our home before they could flee,” survivor Dai Baoyu wrote. Dai was 14 when the massacre occurred. “My big elder brother was caught by the Japanese army when he ran to Xiangyanghutian, and they killed my brother with brutal means. I hid in a burrow all the time, and luckily escaped from death.”

While the museum seared images of the atrocities committed into my head, I felt like it lacked a flowing narrative of the story behind the massacre. There were times when, after seeing pictures of mutilated women and children, I wanted to walk out. Then again, maybe that’s the point.