Nikki Haley, the governor of South Carolina, is the latest Republican to learn how important immigration has become to U.S. conservatives. In her response to the State of the Union address, she argued both that immigrants should be made to feel welcome and that we have to maintain control of our immigration policy. For these comments, she was denounced in some quarters as a moderate who had declared war on her own party's strongest supporters. Both the speech and the reaction offer more evidence that immigration control is becoming a more important, and defining, issue for conservatives.
Why the issue has become central is less clear. It's not because the problem of illegal immigration to the United States is growing; it has fallen in recent years. But that decline has coincided with at least seven factors that have raised the political importance of immigration for the right.
Low economic growth. The economic expansion under George W. Bush was weak and ended in a brutal financial crisis, and the recovery afterward has been disappointing. For most people, incomes haven't been rising as fast as they did in the 1980s and 1990s — and Americans who feel economically vulnerable are more likely to see immigrants as an economic threat.