Does a reference to "...the judge, jury and executioner..." really make sense in armed conflict? Is there really a judge or a jury? There isn't really even an executioner, in the sense of a lawful delegate tasked with carrying out the result of adjudication.
One of the reasons armed conflict is bad is there is really no justice in it and no time for justice. Justice starts to be possible when security is established, and security is established through armed conflict or a strong norm not to get into it -- as we see presently in Europe, where many countries with meaningful territorial losses and weird borders (exclaves, &c) have elected to just never settle those things.
Back when decent civilization was a thing, there were rules of engagement, conduct, the pursuit of security, and strategic goals which didn't include active genocide of civilians.
Now, granted, we've witnessed horrible things in wars that don't match up to order and clarity of my previous sentence. But there were end goals that made sense.
Sorry, genocide, apartheid and the establishment of a religious-fascist state at the behest of Israeli ring-wing fascists that wouldn't put a foot wrong in Hitlers RKF, isn't an end goal I'd say justifies the means, ends or anything in between.
The establishment of security to the denial of all else, isn't the only dish on the table.