Mexico City’s new homosexual civil union law went into effect Friday. My point is not to debate the substance of the issue, but rather to point out that Mexicans are not a people of our imagination, living as we imagine our sainted ancestors did in the shtetls of the old country, but rather real people living through all the moral and social changes of modernity. (As another example, about one-third of babies now born in Mexico are illegitimate.) This sounds obvious, but too many supporters of mass immigration (including the president) behave as though Mexican (and other) immigrants are somehow different or better than we are, and can solve for us the cultural challenges we face in a modern society.