Applying the mores of today is of little value in analysing the actions during World War II. I really would suggest readig the book as it details the spectacular cruelty of the Japanese in one city in China. One city, mind you. Other areas of China experienced much the same genocide, but on a somewhat smaller scale.
The book sobered me up. I now approach analyses of that era very carefully as it was a situation that I have not experienced and I hope never will.
It is inadvertently the best argument for the 2nd Amendment ever written.
One of the sobering reports is of two Japanese officers who had a beheading contest. It was covered in the Tokyo newspaper as sport. They called it a gentleman's draw after each officer had killed 137 chinese.
It was nothing more than sport to them. They deserved the bomb.