I think Japan should have featured in this discussion and perhaps S.Korea as to some degree, they have societies that are "Japan first" or "S.Korea first" if that makes sense. I've been doing some digging and there are many parallels between what MAGA "America First" want and the reality of these other two countries. I think there are lessons that can be learnt from Japan and S.Korea for MAGA.
First of all, these countries are quite homogeneous, that's one thing. Second, they literally prioritise their own citizens over foreigners with regards stuff like jobs or housing. In that sense, beyond "tourism" (being a student or teaching English as the only job) both countries are essentially impenetrable for foreigners.
So I do think there's something here about Japan and S.Korea that massively overlaps with MAGA "America first" movement.
The key challenge with MAGA as compared to these countries is America is not a homogeneous country. Even ignoring any immigrant, America is quite diverse i.e. you have American citizens from different ethnic or racial backgrounds. So that's one thing.
The other thing is America, unlike Japan or S.Korea is in everyone else's business around the world and is an imperial empire meaning it's deeply rooted in globalisation. This to me feels like an insurmountable obstacle to achieving the "America first" dream.
All in all, I think the MAGA movement won't play out as intended as I don't think "America first" dream is achievable in reality. I don't think MAGA can define "America". In Japan and S.Korea, it's obvious who is local and who isn't. In America, you can't just say white is American, or black, or Indian - American can be anyone and it may not be obvious simply from how someone looks.
Furthermore, given how entrenched the US is in globalisation, you will always have foreigners in US Companies because those companies also operate in foreign markets - not just for cheap labour, i.e. these companies literally make money in foreign markets and the money is then funneled back to the US. So you can't avoid having foreigners from this perspective operating within these companies.
Americans don't also have the same genetic heritage given the racial and ethnic diversity so in this sense, I think there are many different underlying inclinations within the population. Looking at the Japan and Korea stuff, one can't help but think that the homogeneity and shared genetic heritage kind of makes everything pull in the same direction and work in "lock step" with the culture. They are quite closed societies from what I'd say. It's funny given how both countries literally have young people refusing to have kids with each other and now face a huge population challenge.
Finally, and this is a big one, discrimination laws are much more black and white in the US compared to Japan and S.Korea. For example, you can't refuse housing to someone in America for the reason they aren't an American citizen, but you sure can in Japan.
You can't refuse entry to a business to someone in America because they aren't an American citizen, but you sure can in Japan.
If you read about all the stuff that goes on in businesses in Japan or S.Korea from the foreigners who've penetrated this space, you'll be like this is kind of what MAGA want but it's all so very illegal within the confines of the US. It's essentially very discriminatory and in Japan / S.Korea, they aren't scared to tell you that you are a foreigner and foreigners in turn are under no illusion as to their status. Let's put it another way, these are "polite" societies, they don't tell you, they simply show you, politely.
America will need a complete re-design to look anything near what MAGA have in mind and obstacles such as legalities and racial diversity may prove insurmountable.