Moral justification for the execution of criminals of war?

[Aegon]

Pretty much every study on whether the death penalty is a deterrent are too methodologically flawed to draw conclusions one way or another. Especially because most states have not executed any prisoners in recent years. One cannot study the impact of executions when they are hardly ever imposed, and it is difficult to separate any impact of the death penalty from the large number of other factors that affect the amount and kinds of crime.

I'm opposed to the death penalty in the U.S. because, if there is even the slightest chance an innocent person is found guilty and sentenced to death, that's enough of a reason to axe the idea of the death penalty entirely.

Even for a war criminal, I generally don't believe an eye for an eye is the correct ethical approach. And what does it mean to be a war criminal in the 21st century? Every living president is a war criminal. Look up "Obama 90%." Most war crimes are done remotely these days.