The Man Who Ended History: A Documentary by Ken Liu

I recently posted a link to some of the nebula nominees that are available to read online. And today I decided to read one, so at random i clicked a link and found myself reading The Man Who Ended History:
A Documentary.
It is set in the near future where scientists have discovered how to time travel, in a way. More accurately, they have discovered how to allow people to witness the past. However, once witnessed that event or time can never be seen again. The Bohm-Kirino particles that make it possible are destroyed in the process.
Evan Wei and his wife Ademi Karen are the discoverers and developers of this technology, and Wei has a particular interest in one specific time and place. Pingfang, and the actions of Unit 731.
Before reading this story I had never heard of Pingfang, it has also been called The Asian Auschwitz, so that will give you an idea of what went on there.
Wei is determined to bring those events to light, to a wider knowledge. But there are those who want to keep the past in the past.
I found this a fascinating read, not always an easy one, but one full of interesting ideas and questions. Like, who does the past belong to? And is there any point in bringing old crimes and atrocities back to the world?
The story it self is told as though a transcript of a documentary, which is useful as it allows for other sources to be quoted and used without feeling forced, but it also means other is a bit of a distance between the characters and the reader. A deliberate choice I would feel, this is a story that wants you to think and so gives you the space to do so.