That's an interesting article, I hadn't read that one. From the academic standpoint there is still quite a lot of debate about what causes radicalization and/or participation in armed groups where this article seems to be taking a particular view (I'm not sure how effective the proxies are that the author used, nor if they are arguing on the basis of little correlation as disproving causation).

To you and /u/zzzztopportal's point...

Japan and Vietnam were bombed tremendously in WW2 and the Vietnam War. Hell, Japan was outright nuked

Japan fought fanatically in WW2, with entire armies refusing to surrender. Japan famously unleashed suicide attacks like the kamikaze.

The Vietnamese fought even when utterly outgunned and suffered massive casualties in open warfare. More ordnance was dropped on Vietnam than in WW2.

And yet, both nations today are extremely pro-US, show no signs of radicalization or terrorism (internally or outwards towards other nations, let alone the US).

The idea that killing people results in others going into a bloodlust for revenge is ridiculous: we aren't guttural animals nor is the characterization of certain peoples as thus accurate, realistic, honest or fair