There is a long history of Christians in the Israeli military, in fact there was (is?) a specific service for non-Israeli citizens called the MACHAL (Hebrew acronym of ‘Mitnadvei Chutz-La’Arets’; foreign volunteers). According to the MACHAL history I’ve read, 70% of pilots in what later became the air force equivalent in the IDF were MACHAL in 1948, and this meant that business transpired in English instead of Hebrew out of necessity. Seems an inordinately high amount of naval officers at the time were also non-Jews. As these were specialized tasks of experienced WWII officers brought to a country moving from several political and ethnic militias to a professional military, this is neither surprising nor should it be embarrassing. The US probably wouldn’t have won our revolution without help from French and Prussian officers.
Some MACHAL were Jews but many, perhaps a majority (?) in the early days of Israel were not. I don’t mean to imply that all 70% of MACHAL pilots were non-Jews, but the % of non-Jews would have been high. Some 119 MACHAL died in the '48 war.
My boss was an Israeli military volunteer in '67, '73 and circa '91. He also served as a trainer for paratroopers in some intervening years. He is an American of Irish Catholic stock (he made up a shamrock/Star of David insignia which is apparently still used in modified form as a unit insignia of some sort, with the origin lost to most of the people wearing it). He tells me there were thousands of non-Jewish volunteers, especially discharged Vietnam vets during & after that war. He told me the Armegeddon-oriented Christians are discouraged from joining & they try to sniff them out but that some semi-(or completely) conceal their intentions & end up in the service. Apparently this creeped him out as these people are LOOKING FORWARD to a final battle and were unnaturally calm when Iraqi SCUDs were incoming…
You can also volunteer as a technically-not-doing-military-work military base grunt via Sar-El, which also runs a program for non-Israeli Jews (that is, Jews w/o formal citizenship) to join the IDF proper. According to my boss if you have valuable military experience & go via Sar-El, you can well end up for all intents and purposes in the Israeli military if you wish. Sar-El is the volunteer-in-Israel group run by the World Zionist Organization, which never changed its name from generations ago and sounds quite anachronistic (if not totally made up by anti-Semites!). It’s easy to find this all on the web.
Add in those Russian immigrants and there’s every reason to believe there are thousands of non-Jews currently serving in combat or combat training roles in the Israeli military, with maybe hundreds more in support roles such as medics via Sar-El. And I read the OP as asking about non-Jews now and historically, so I think the SLA merits mention (I also don’t believe those guys suddenly incorporated themselves into Lebanese society with their bitter enemies; I should think ties to Israel remain).
I would not compare Mexican labor in the US to the importation of Ghanians, Thais, Koreans, Turks, etc. to work (for the minimum wage of about $2/hr) as replacement Palestinians in Israel. On the plus side, the Israeli system, which is much closer to the way Gulf Arab States work things (high irony and I should think embarrassment) is at least ‘honest.’ Ours is not. These are guest workers invited in for specific jobs for specific permits. Looking at the geography, one strains to see how a Thai gets into Israel to work construction ILlegally. Almost all of this is legal, and in fact ‘necessary’ to the Israeli economy if you accept the effective lockout of a lot of former Palestinian labor. These are people brought into a country who have no cultural tie to the area (for that very reason), have no plans or right to stay beyong their immediate usefulness, and are desperate to get money home to dependents. It still lends itself to horrible abuse, as I witnessed first hand when I worked in Qatar, which issues much the same sort of labor permits. (No job? Sponsor doesn’t like your face? Bye-bye.)
We have nothing to be proud of with our Mexican labor, but we’re talking about people crossing a porous border & in many cases looking to settle and restart life here (while also remitting funds home)… often in territory with Spanish place names that used to be part of their country, with established Latino populations. And, hey, in many cases we let them. Have a child here, in fact, and your tot’s an automatic citizen (not a big flagwaver/patriot type but I consider that the Best Law Ever!). No Qs about your parents’ relgion or ethnicity. Those are huge differences IMHO.
Finally on that point, there are Mexicans working in agriculture (and restaurants) in nearly every state now, it’s not just the West any longer. Pennsylvania’s a huge mushroom grower, and Kennett Square (a town) has huge numbers of migrant Mexican workers, just as one example.
Finally, nations such as Tunisia, Morrocco, Yemen, Syria (none of which really have huge populations) with Jewish populations in the thousands (or tens of thousands until emigration mainly to Israel) also have compulsory military service for male youth. Until someone posts a cite stating laws to the contrary (i.e. barring Jews from national service), we have to proceed from the assumption that hundreds or thousands of Arabic Jews (Jewish Arabs?) have served and are serving in their nations’ armies. When I was in Tunisia it seemed the Jews there were pretty well intigrated into the society as a whole, and I don’t think there’s exactly a big draft dodging movement there coming from any quarter.
Considering how touchy some of these subjects are I think we all get a big pat on the back for staying quite civil…