I think it kind of makes sense if your country is potentially under threat from a bigger, unfriendly neighbor, like Finland for example.

In the US, two year mandatory service would result in a standing army of about 15 million men if I'm doing the maths right. That seems a bit ott for a country whose military is already op.


1. so long as nation state level armed conflict is a thing, we need militaries
See above. I think it's pretty unlikely the US is going to be subject to a suprise invasion by Canada eh.



2. given 1, unless everyone serves, it'll be the poor that serve
Well, that does seem bad I guess. Though otoh, in a real war with a real draft you'd hopefully avoid that.



3. given 2, the disproportionately undereducated are pumped full of pro establishment/status quo propaganda in isolation from everyone else
So it's better to have everyone equally pumped full of nationalist propaganda?


4. given 1-3, a volunteer armed forces is prone to erode bonds between lower/working class and middle class, leading to polarization.

5. as a bonus, it's commonly said that one of the most valuable things gained in college is the connections-- imagine the increase in social mobility if everyone was mixing with everyone for 1-2 years in their late teens/early 20's.
Depends how many people are in it. If it's well under 1% of the population, as I believe is the case in the US, it seems unlikely to be an issue.

Also, it isn't obvious to me that an armed forces is a place for social mobility and making lots of friends, at least not on the same level of college. Seems much more structured. If it were a meritocracy, you'd have a stronger argument imo. But most armed forces make the advantaged kids the officers and the less advantaged ones the grunts. That would seem to reinforce those divisions, not remove them.