Did not even know that a foreign national could join the American Armed Forces until a few years ago.
Handy way for another government to get our troop movements.
I don’t think the “benefit” is worth the “risk” in today’s environment.
I believe Filipinos can join and NOT pay Social Security. They get a pension and live like kings in the Philipines when they retire.
As far back as the 90’s the US Navy allowed Mexican citizens to serve. I worked with a couple of them.