THE SAMENESS OF OTHERS:

[H]ostility to immigrants, even among the native born, is least pronounced in places with the biggest immigrant populations. In Inner London, a truly international city, only 16 percent of respondents admitted prejudice, a 17-point decline since 2000. Outer London likewise registered a decline.

England's experience is perfectly consistent with America's, where the most anti-immigrant states are those with the fewest immigrants -- and vice versa. USA Survey reported some years back that in New York and California, the most immigrant-dense states, far fewer people felt that "immigrants take away American jobs" and far more felt that they do "jobs Americans won't do" than in immigrant-poor states such as Alabama, Mississippi, Indiana, and, my own, Michigan.

Contact with immigrants humanizes them, making it harder to scapegoat them for existential anxieties created by a fast-changing world. It also creates a co-dependence, making it harder to fixate on the downside of foreigners when, say, professional moms rely on them for baby-sitting or accounting or other services.

But there's a deeper reason, too: Much anti-immigrant sentiment does not stem from racism, nativism, xenophobia, or any other affirmative hatred of foreigners -- although there is certainly an element of that. Rather, much anti-immigrant fervor stems from what George Mason University's Bryan Caplan has dubbed the "status-quo bias" -- a preference for the status quo because it is the status quo.

People have a natural affinity for a world that they know because it is hard for them to imagine the alternative. And what they've known are linguistically, culturally, and ethnically/racially homogeneous social arrangements stemming from a tribal or kinship-based past. Active bigotry and preference for the ethnically familiar are not the same thing, and advocates of immigration, myself included, who conflate the two do their cause no favor.

But as mass migration, still a relatively recent phenomenon in historical terms, makes cosmopolitan communities more of a norm, the status-quo bias will ineluctably swing. As natives begin to directly observe and experience the advantages of diversity, acceptance of immigrants will increase, even turning into an open embrace perhaps.

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