This isn't really that controvestial. I am surprised anyone takes exception to it. But war presents the opportunity to kill wrongly, and does so as much as it does justifiably. And in the middle of a war zone, the opportunities will nearly always present themselves. Remember Iraq? Even the charges that didn't see convictions were only lost due to lack of evidence (and some claim that lack was because of the investigation being hindered). It is hard to prosecute and know.
But here, there would be no hiding it among the other bodies. We would know someone committed a crime. In war, we can excuse it as collateral or even lie that it was really the enemy, or just that we thought it was the enemy. Logically, that makes it harder to even know there was a crime, and as such easier to commit.