very high net immigration rates (the per capita ones) simply are not possible for large countries. fun number trivia: to have a net immigration rate as high as luxembourg’s, the US would have to import all of Italy or France every 10 years. to get a net immigration rate as high as Qatar’s, the US would have to import all of the Netherlands every year.
this is a good thing, though! it means big countries can absorb comparatively more migrants with less short-term disruption–the US has tons of small towns and cities people can move to, form immigrant communities in, and start living their lives.
you could turn the question around and ask, ok, but what would the US look like if it suddenly had a huge amount of immigration from poorer countries? wouldn’t it be poorer itself? well yes, on average, it would. because moving to a new country doesn’t instantly give you a salary that’s average for that new country. but the people already living in the US wouldn’t become poorer–they would probably become richer, because immigration is a net benefit to the economy. and the people moving would become richer over time. so the actual amount of wealth available to everyone would increase, even if on paper the US per capita gdp went down. obviously the wealth of new immigrants would go up faster if there was a UBI available to them, and in that respect, a UBI could be an important equalizing tool between old citizens and new citizens, a valuable source of capital to start new small businesses or to invest in education.
So the question (in the context of the original post) is: in an open borders situation, what actually imposes the limit? Especially in an open borders + UBI situation.
Like, the US is really far away from open borders right now. We could (and probably should) double or triple immigration while still being really far away from open borders. And that’s because so goddamn many people want to immigrate. Gallup says 150 million people would move to the US if they could. (And that’s without the addition of UBI as hypothesized in the original post!)
And obviously that would be fucking unmanageable over a few years. So like one response here is to say yes, we’d never allow a hundred million immigrants in a five-year period. And that is true. But that’s denying the hypothetical of “open borders”.
So if we did move to an actual open borders situation, how many people would actually move here? It probably wouldn’t be 150m; talk is cheap. But would it be 50m? 20m? Honestly, 20m over five years sounds manageable. (There are currently about 750k green cards per year, so that would be quintupling the flow.) But 50m definitely isn’t. Would the inflow be self-limiting? What would create the limit?







