Donald Trump said something pretty remarkable, even for him, about illegal immigration at tonight's Republican presidential debate, claiming his focus on the issue was the reason it was being discussed on the campaign trail. "If it weren't for me, you wouldn't even be talking about illegal immigration," Trump told Chris Wallace, one of the co-hosts of the debate. "This was not a subject that was on anybody's mind until I brought it up at my announcement."
The polar opposite is the truth. "What I say is I say," Trump claimed, but on immigration what he says is what plenty of other Republicans have said too. In fact, one of the big reasons Trump has traction in the Republican race is because of his extreme position on immigration. The issue's animated the Republican base for several cycles. Republican voters took their time coming around to John McCain in 2008 in large part because of his "maverick" stance on immigration—he has supported "comprehensive reform," a catch-all term for efforts to create a path to normalize the status of illegal immigrants in the country, make it easier to work in and immigrate into the country, and militarize the border. The Republican candidates spent much of 2012 painting each other as soft on immigration, which may have come back to hurt eventual nominee Romney's chances in the general election.
President George W. Bush's campaign in 2006 for comprehensive immigration reform helped finally turn a lot of congressional Republicans away from him. Republicans, with help from Democrats, torpedoed Bush's efforts. Even Barack Obama, the eventual Democratic nominee and president, helped.
In his announcement, Trump claimed Mexico sent drug dealers, rapists, and other criminals across the border. While he blamed political reporters for misrepresenting his comments, it's not surprising so many people interpreted them as attacking the general population of Mexican, and Latino, immigrants. Over the following weeks, NBC News, Macy's, and several other companies cut their ties with Trump. But he kept rising in the polls because, as in previous elections, base Republican voters respond well to anti-immigration rhetoric. Trump isn't the reason his anti-immigration rhetoric, and economic xenophobia more generally, is well-received by some Americans. In an interview with Vox.com, socialist Bernie Sanders, running for the Democratic presidential nomination, called the idea of "open borders," or fewer immigration restrictions, a right-wing ploy to suppress wages. Sanders and populistus like him may not put it the same way as Trump, but they're as comfortable with rhetoric that suggests countries like China are "beating" the U.S. because of free trade as Trump is.
There are, of course, plenty of reasons more open immigration policies, up to open borders, are "good for America." But xenophobic economic populism and anti-immigration rhetoric are easier to play at the polls. Trump's taken advantage of the phenomenon, but he's certainly not the reason for it.