The problem is, while I completely agree with that argument, I don't buy it in the slightest.
Wars should have standards, but, de facto, they don't. No war does. Just look at Iraq War: it has been fought in modern times, with "intelligent" weapons, by a country that supposedly stands for freedom and justice, under the eyes of the whole world, and yet it still has caused horrific atrocities.
Like that 14-year-old Iraqi girl that was gang-raped by a bunch of American soldiers who then murdered her and her whole family to try and cover it up. Like the countless Iraqi people who "disappeared", were kidnapped, imprisoned and tortured because they might have some kind of vague connectiong with terrorists possibly maybe. Like terrorists using civilians as human shields. And so on and on and on.
That's what war really is, that's what it has always been. While it should have standards, I find it incredibly naive to actually expect them. The only way to avoid such atrocities is to avoid war, period.