I asked people about the places to which they had traveled in the last 10 years: Canada, Mexico, Australia, Asia, Africa, Europe and South America, and whether they had eaten a meal at an Indian or Japanese restaurant in the last decade.
The questions helped differentiate white voters who chose Barack Obama in the 2008 Democratic primary from those who chose Hillary Clinton. The more likely people were to experience other cultures — through travel or food — the more likely they were to vote for Mr. Obama, even controlling for things like income, education, personality, racial attitudes and city living. As J.D. Vance recalls in his memoir, “Hillbilly Elegy,” comments about voters in parts of the country “clinging to their guns and their religion” didn’t help Appalachian residents warm to Mr. Obama. He was different from them, and he reminded them of it all the time.
As the 2016 campaign unfolded, Donald J. Trump drew on this tendency to mistrust those who are different by saying he would keep various outsiders away. To see whether this had appeal, I asked 3,000 people the cosmopolitanism questions and found a pattern. White Republican primary voters were more likely to vote for one of the other 16 candidates in the race instead of Mr. Trump if they had traveled abroad or gone to an Indian or Japanese restaurant in the last 10 years. In some cases, the differences were quite large.
Mr. Trump fared worst among white G.O.P. primary voters who had been to Asia, Africa or South America. These voters were 23 points more likely to choose one of the other candidates in the race. Those who had been to Europe, Australia, Canada or Mexico or had eaten at an Indian restaurant were also less likely to choose Mr. Trump by 10 to 12 points. The differences for eating at a Japanese restaurant and hunting were smaller, and there were no differences among those who had played softball on a team.