I have a lot of experience of soldiers and junior officers competing to get posted into units scheduled to deploy on operations.
In the Army there are three types of people: psychopaths, brainwashed patriots, and scared kids. You're describing the first two, and the second one will become the third as soon as bullets start flying.
I imagine you're talking about Navy/Airforce? They tend to be normal intelligent folks for sure. Line units in the Army are a completely different world.
I think you're working off ancient stereotypes. Modern land warfare is highly technical and extremely mentally and physically demanding. A modern professional army doesn't have any room for psychopaths, brainwashed people, or scared kids.
Look at all the effort the military goes into in combating 'brainwashing' - mission command and encouraging people to use as much initiative as possible.
Ah, that makes sense. Let me tell you a thing about the US Army vs. our European counterparts. The Army is essentially a "last ditch" choice for impoverished kids with no other option in terms of jobs or education. The smart ones join the Air Force or Navy, and the dummies get filtered into the Army infantry. I know because I was one of them. I went through basic training with a convicted drug dealer and an attempted murderer. It's technically a "volunteer force", but once you sign up you are bound as a slave by law for the length of your entire enlistment. (Obviously this does not apply to officers)
Contrast this with European militaries which are 10x smaller, and thus only accept an elite core of people who are able to make the cut. The result is a completely different culture and force. I have no doubt that the British Army is full of complete professionals, as anyone who wasn't into it would quit or be kicked out or not even make it through selection in the first place. It simply doesn't work that way here.
Please enlighten us then. If you don't have data or personal experience to share, do you have anything of value to contribute?
Immigrants to nations have fought for their adopted homes with ferocity in the past. It make sense, really - this is somebody who liked (loved, even) the country so much that they worked hard to get there, as opposed to someone who happened to be born there and so is there by default.
Also, one complication to consider in your example of the American in Germany is that US citizens who join foreign militaries risk losing their US citizenship. Of course, for some people that's not a problem (there are a lot of accidental US citizens), but for others and their families it could pose an issue.
https://travel.state.gov/content/travel/en/legal-considerati...
The first counterexample that came to mind: to be exterminated without even putting up a fight.
I'd judge surrendering your freedom and your property without putting up a fight as "more disgusting than war." Allowing an innocent ally to be conquered probably also qualifies. There's really quite a lot of stuff that is "more disgusting than war." But people can feel free to choose what they're disgusted by...