Don’t think you have caught the point.
The oil embargo was to stop their conquering of China.
Much like the US in the 1970s, a decision was made that no embargo of oil was going to dictate national policy, so they did not stop their empire building, but instead sought additional oil.
It’s fun to think religion or morality or whatever decides wars since 1900 or so, but it’s oil. Pretty much it’s always oil. View things thru a prism of oil and you’ll understand.
So that's why the Japs committed all those atrocities. It was because of the American oil embargo. Maybe America should apologize to the Japs.