"
Dulce et decorum est pro patria mori."
Discuss why you need to be in a uniform, or be killed by someone else, for this to be appropriate (for whatever values of appropriate you feel it should be,
vide Wilfred Owen). Discuss, further, why fighting an asymmetrical war under the stronger side's rules of engagement is the right way
pro patria mori (because trust me, in that scenario, it's equivalent to given). The difficulty you find doing that is the difficulty you get trying to solve the OP's question(**).
A lot of people join the U.S. Army because "it's a job" - and it's one of the best they can get (what with the health care and the pay and the free training, especially to shore up some of the things they didn't get [to] in secondary school). But even more do it because of the "pro patria mori" bit - or at least the "pro patria servo", knowing death could be the service required. Now think about people whose living conditions are so much worse than "an American with a roof" (and no prospect for improvement), and maybe have reasons for revenge(*), and induce from there.
* and if that's the case, if there are two options, both of which will get you killed, but one of which has a 5% chance of killing one of the enemy, and the other of which has a 30% chance of killling 40 or 50, which would you expect people to choose?
** by the way, I spent 20 years+ of my life trying to get to the point where I saw a value in living that exceeded "two or three of my family would be so hurt if I wasn't here". It's an ongoing struggle. So my belief in the "will to live" being something that can be made unviolable ranks right up there with my belief in the Flat Earth.
Long live the Republic-k. -- Major General J. Golding Frederick (tSCoSI)