Whats relevant though is that most soldiers obeyed the orders and preferred to commit war crimes. Even in the US military which has a strong moral ethos (or likes to portray itself that way which for the common soldier is the same thing) But what about all the other, smaller countries?
I don't feel we've become profoundly nicer since then.
We've since developed PGMs which allow us to minimize collateral damage more than ever before. We can destroy strategic targets of military interest with pinpoint accuracy. People that commit war crimes are reported by their fellow soldiers and justice is (usually) served. Sometimes war criminals are pardoned even after being turned in (like Gallagher), but this is rare and usually results in national outrage.
Committing war crimes has effectively been the national defense policy of last resort since WW2. That's what the nukes (and formerly chemical and biological weapons) are for. The implicit threat is that the US will massacre your civilian population.
And I don't mean that as any special criticism of the US. Most countries have a similar attitude of the rules of war going out the window when things get bad enough.
I'm not sure about the "square full" bit.
So..how do you explain, to give but one example, the hundreds of thousands the US killed in Iraq?
If insurgents hide and fight among civilians, civilians are going to die in the process of destroying the insurgents. It's like cancer - you can't kill cancer without killing tons of healthy innocent cells around it.
I don't necessarily agree with the US's prolonged occupation in the middle east, but it's highly disingenuous to imply US military leaders are commanding their soldiers and pilots to intentionally kill civilians.