Sensible Thinking On Immigration From Immigrant Eugene Volokh
As @WalterOlson tweeted, "advocates of liberty can't afford to ignore the future-polity angle."

Constitutional scholar, law professor, and small "l" libertarian Eugene Volokh blogs at Volokh.com:

I sometimes pose for my liberal friends a stylized thought experiment. Say that they live in a country of 3 million people (the size of New Zealand) where 55% of the citizens are pro-choice and 45% are pro-life (1.65 million vs. 1.35 million). Now the country is facing an influx of 1 million devoutly Catholic immigrants, who are 90% pro-life. If these immigrants are let in and become citizens, the balance will flip to 2.25 million pro-life to 1.75 million pro-choice (56% to 44% pro-choice); and what my friends might see as their fundamental human right to abortion may well vanish, perfectly peacefully and democratically.

It's unlikely that any constitutional protection will stand in the way: Even constitutions can be amended, and new judges can be appointed. Nor can one rely on "education" or "assimilation" -- what if the immigrants simply conclude that their views on abortion are just better than the domestic majority's? I think many of the current residents may rightly say "We have nothing against Catholics; but we don't want our rights changed by the arrival of people who have a different perspective on the world than we do."

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.

via @WalterOlson