This line of thinking comes up often on HN but it ignores the central reason for governments to enact borders, a rather modern invention. Governments (at the behest of businesses) enforce borders so that labor cannot effectively organise. A border exists often for workers only, but is mostly a legal fiction that corporations can easily navigate. The most common example for the Americans reading this is NAFTA, which m…
This is backwards, and I'm having trouble understanding how a more diverse, more transient population would find it easier to find common interests and unite. Suppose a factory unionizes - without borders, the owner will find it easier to import non-union workers. While moving a factory is challenging regardless of borders - it's a big, heavy thing, tied into local infrastructure and supply chains. It's even reflected in the rhetoric - "immigrants will do the jobs Americans won't".
It's also reflected empirically: Whole Foods' heat map says lower rates of racial diversity increase unionization risks - https://www.businessinsider.com/whole-foods-tracks-unionizat... (unpaywalled: http://archive.is/1khJw)
And in the strong Danish unions as far back as 1981 (https://mattbruenig.com/2021/09/20/when-mcdonalds-came-to-de...) when Denmark had only 3.02% of immigrants and their descendants (https://en.wikipedia.org/wiki/Demographics_of_Denmark#Modern...)