There Donald Trump was onstage Monday night in Houston, yet again spreading nonsensical lies about immigrants bringing crime to the country. He insisted—"without evidence," as the newspapers say—that the Democrats had "something to do with" the caravan of desperate Central-American immigrants making the long trek across Mexico. Donald Trump called those people “an assault on our country, and in that caravan you have some very bad people and we can’t let that happen to our country." He and Vice President Mike Pence have claimed the caravan contains "unknown Middle Easterners," a conservative ally of the president told the Washington Post the group of 7,000 amounted to a "massive horde trying to bust our borders," and Republican Congressman Matt Gaetz even implied the caravan might be funded by liberal mega-donor George Soros.

That these claims are baseless is besides the point, because the point is to paint all immigrants as gang members and animals and harbingers of chaos. That's why Trump said over the weekend that sanctuary cities in California were "rioting," why he said in Houston that immigrants were inclined to "carve you up with a knife." Trump and his allies want to make ordinary voters afraid, and the vaguer those fears, the better. One 75-year-old Republican in Minnesota told the New York Times she worried about migrant gangs occupying lake houses.

The lies and the racism aren't even the worst part—the worst part is that this is a conscious strategy. This is how Trump and the Republicans think they can win the upcoming midterm elections, and the rest of us just have to hope that their dark vision of America is wrong.

“Voters are motivated by fear and they’re also motivated by anger,” is how Trump ally Newt Gingrich put it in an interview with the Washington Post, saying of the caravan, "They are trying to invade my home.” A former Trump campaign adviser named Barry Bennett was even more blunt in comments to the same paper, calling that caravan a "political gift" and adding, “I wish they were carrying heroin. I wish we had thought of it."

None of this is connected in any way with policy. Though Trump has called on voters (via Twitter) to "blame the Democrats for not giving us the votes to change our pathetic Immigration Laws," as usual it's hard to figure out what laws he wants changed. During the immigration debates of the last two years, Democrats supported compromises that would have provided additional funding for border security, while Trump has insisted legal immigration be slashed, which has nothing to do with the southern border.

A few thousand migrants slowly marching through Mexico do not represent a real threat to the US. It's merely a hook on which Republicans can hang their ugly racial political appeals—not that they needed one. Even before the caravan was an issue, the GOP was unleashing racist campaign ads, particularly against black candidates. One called a Democrat of Palestinian descent a "security risk"; another accused a Democrat of being unqualified for Congress because he once made a rap album (that Democrat, Anthony Delgado, was also a Rhodes Scholar).

Racist ads are certainly nothing new from the party that brought us the infamous Willie Horton spot in 1988. But this time Republicans betting everything they have on prejudice—they aren't campaigning on the tax-cut bill that was their signature accomplishment of 2017, and when they do talk about healthcare, it's to lie about their actual agenda. When you take away healthcare and taxes, the only remaining planks in the Republican platform are all about evil brown people pouring across the border to kill white people.

Immigration is obviously a highly partisan issue, but it's not necessarily a winner for Trump and the GOP. In a recent op-ed for the New York Times, a pair of political scientists argued that while Trump did better in 2016 among "anti-immigration whites," his hardline stance likely inspired a "liberal backlash" and drew more tolerant voters to Hillary Clinton. "Xenophobic whites have long been reliable Republican voters, whereas less intolerant whites have tended to waver in their presidential voting," the authors wrote. "Democrats may therefore have more to gain than Republicans by continued political conflict over immigration." This dynamic seemed to play out last year in the Virginia gubernatorial election, where the GOP (and Trump in particular) emphasized crime and migrant gangs and ended up getting their clocks cleaned.

It's hard to extrapolate a whole lot from regional elections, since candidates and issues can vary so much across locales, but it's telling that Republicans thought the path to victory in Virginia was xenophobia—and they were wrong. They're now trying similar strategies all over the country, as Trump migrates from rally to rally saying increasingly outrageous things that appear to have been written by Breitbart SEO specialists, full of words like riot and crime and illegals and sanctuary cities and MS-13. Who knows if Trump believes what he's saying. The point is that he thinks so little of Americans that they will.