If the number of people who can live in cities is artificially limited, the price per person for legal housing will increase to the point that no poor person can afford it.
Eugene Volokh and Ilya Somin have started an interesting conversation on immigration at the Volokh Conspiracy blog. The initial exchange centered on the potential for immigration to alter the social norms and formal laws in the destination country. Volokh writes:
The bottom line is that for all the good that immigration can do (and I’m an immigrant to the U.S., who is very glad that America let me in, and who generally supports immigration), unregulated immigration can dramatically change the nature of the target society. It makes a lot of sense for those who live there to think hard about how those changes can be managed, and in some situations to restrict the flow of immigrants — who, after all, will soon be entitled to affect their new countrymen’s rights and lives, through the vote if not through force.
…Letting in immigrants means letting in your future rulers. It may be selfish to worry about that, but it’s foolish not to. For America today, that’s actually not that much of a concern, because we’re a huge nation whose culture is already so mixed (for which I’m grateful) that even millions of immigrants won’t affect it all that greatly, at least for quite a while. But for many smaller and more homogeneous countries, extra immigration means a fundamental change in what the country is all about, and perhaps what the citizens’ lives and liberties will be like. And even for America, the influx of millions of new citizens — both the potentially legalized current illegal immigrants and the many others who are likely to come in the wake of the legalization — can affect the society and the political system in considerable ways. It seems to me eminently sensible to be concerned about the illegal immigrants who may well change (in some measure) your country even if your ancestors were themselves illegal immigrants who changed the country as it once was.
He [Volokh] underrates the extent to which such “political externalities” can be combated by means short of banning immigration, and is also too ready to subordinate the rights and interests of potential migrants to those of current residents.
…All of the above assumes that the immigrants would change the political system for the worse. But, obviously, they could just as easily have a beneficial impact. Precisely because of their painful experience in less free or less prosperous societies, immigrants will sometimes have a better understanding of what makes their new country successful than many natives do. This isn’t always true, of course. But the possibility that immigrants might actually improve the political system needs to be carefully considered and weighed against the danger that they might have a negative impact.
Somin also discusses options for innovation in the rules that would address concerns about social disruption from immigration:
There are many ways to reduce potential negative political effects of migration short of banning immigration itself. The most obvious is to deny the immigrants in question the right to vote. Both the United States and most other nations already impose waiting periods before new immigrants become eligible for citizenship (currently five years in the case of the US). If necessary, the five year period could be extended to ten years, fifteen, or even longer. We could even grant permanent residency rights to people who are ineligible to vote for life. Living in a country for many years without the right to vote may seem like an injustice. But living that way in a relatively free and prosperous society is still far better than living in a poor and oppressive Third World country – in many of which the citizens also lack any effective political influence.
Waiting periods for citizenship both eliminate the possibility of immediate political change and give time for the immigrants to become more assimilated and embrace more of their new country’s values. It’s true, as Eugene notes, that such assimilation isn’t always completely effective. But history shows that it does have a profound impact over time.
The impact of immigration on a society’s laws and social norms is a controversial topic, but it is also one that needs to be addressed if migrants and destination countries are going to capture the substantial benefits from freer global migration.