A border is where the control of one sovereign ends and another’s begins. In the ideal case where individuals are sovereign, borders are in the simplest case just the boundaries of your home. You receive visitors based on whether you personally like and trust them (directly or indirectly). Sometimes the help of others can be useful in fending off unwelcome visitors. People can then organically and voluntarily federate together at any scale, ranging from an apartment building doorkeeper to continent wide military defense.
Alas, today’s sovereigns are mostly states reigning over many individuals, ranging in size from Monaco and Tuvalu to Russia and India, where the largest can be many orders of magnitude larger than the smallest. They too exert control over who they want to let inside their domains. Being large, collectivist, impersonal bureaucracies, they are much more hamfisted and blunt about it than individuals in their own homes. As always, this leads to inefficiency, unfairness and tragedy.
I’m directly affected by this in my own life, to a much larger extent than that visa policies and border checks of course make it harder to go places: I can’t invite a dear friend to my own home because some bureaucrat who has never even met either of us says no. I can’t live with my beloved because some rule book that is applied with a broad brush to the majority of the earth’s population requires us to jump through ridiculous hoops, wait for years and in the best case even then be pretty limited in our movements. How dare they? Why do they do this? And, why is it so pervasive?
The main reason is free stuff (and other common goods). That is, subsidized goods like infrastructure, healthcare, legal system and direct welfare payments. An all-you-can-eat buffet with no admission fee. In lieu of fees, for all of the buffet to not be gone in an instant, admission has to be regulated some other way. Enter blunt rules and bureaucracy.
(Many costs – as well as benefits – of immigration are not of a direct economic nature. Instead, they are consequences of differences in such things as in-/out-group boundaries and norms. But without the subsidized economic pull factors these mostly become moot, as migration would be smaller and very different.)
All places with some significant amount of subsidized goods heavily regulate immigration. Even extreme and ideologically driven ones – like Sweden in the 2010’s – exclude the majority of all humans. All the political parties, including the ones said to be pro immigration, think too large numbers of too poor immigrants are too costly. When in power, these ”pro immigration” parties therefore enact and enforce policy that stops the vast majority of all such people from entering the country. By force. No matter how much they want to come. No matter if their lives depend on it.
And all the political parties, even the ones said to be anti immigration, tend to welcome people who are wealthy enough.
So all the loud political battles, the bombastic rhetoric, all the vitriol – is about whether to forcibly keep out something like 82.64% versus 82.67% of humanity. That is, even the most radically opposed of the parties in parliament agree on what immigration policy should apply for about 99.97% of the number of people on earth. The disagreement is about the remaining 0.03%.
This unity is not as surprising as it may seem, because almost all (I’m guessing north of 99%) voters agree. They all want subsidized goods and they all want to keep the rest of the world away from most of it. All of these voters have limits above which they think certain types of immigration are too costly, but disagree on where exactly these limits are.
Yet again, large scale, centralized, faceless collectivism is to blame. A state extracts resources by taxation and uses and redistributes them along the lines of its internal power games. In order to do so, they crudely divide people into groups by superficial characteristics using bureaucratic rules.
What if instead society could be individuals interacting with each other as individuals? And doing so voluntarily, how and if they wanted to? There wouldn’t even be such a thing as migration policy. Without involuntary taxation there would be little to exploit. Anyone could go wherever they were welcome by people who wanted to show them hospitality or sell or rent to them. The way it usually already works within countries.
Almost everyone insists on doing things the current way, though. Then lines will be drawn somewhere. The results will never be fair or good. Within this paradigm, to keep society functional and not bankrupt it, closer to 82.67% than 82.64% of humanity must be excluded. (Even within the paradigm, however, many things could conceivably be done to increase fairness, efficiency and freedom. Such as a sponsorship system or a basic thing like making sure to always consider incentives.)