system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5:Why is the Rape of Nanking/Nanjing glossed over in US history textbooks?

Or is it? I went to high school in the mid 2000s and I remember being shocked my World History textbook literally had only one sentence on it. Something along the lines of "The Japanese invaded China...something something...now called the Rape of Nanking." End. Finished. And yet, we spent so much time learning about Hitler and the Holocaust. Can someone explain why? Does it have to do with diplomatic relations?
gpt
Wars altogether are glossed over in US history books. There just isn't enough time to put everything interesting or notable in them - the Japanese invasion of China was, you know, the Japanese invasion of China. It didn't significantly involve American efforts or affect the war from our perspective. 

The Holocaust and the Nanking Massacre are completely incomparable. Incomparable by a matter of multiple digits.