Jacquelyn Martin / AP

Donald Trump’s ongoing purge of the Department of Homeland Security marks another milestone in his transformation of the GOP into an exclusionary party defined by its hostility to immigration in particular and demographic change in general.

Trump’s move to install more hard-liners at DHS—headlined by his dismissal of Secretary Kirstjen Nielsen and the withdrawal of his nominee to head Immigration and Customs Enforcement in favor of “tougher” leaders—signals his determination to implement more draconian responses to the Central American migrants seeking asylum at the U.S.-Mexico border. While some congressional Republicans have raised alarms about the magnitude of the turnover, hardly any have publicly complained about the direction of Trump’s policy.

Some GOP lawmakers still resist the most militant expressions of Trump’s restrictionist inclinations—several balked at his recent suggestion that he would close the U.S.-Mexico border, for example. But the muted response to Trump’s DHS purge testifies to the decline of any coherent, structured resistance within the party to his overall course on immigration. Just over halfway through Trump’s first term, the only question left in the GOP is not whether to follow his lead toward greater hostility to immigrants and diversity, but how far and how fast to move along that track.

“The party is going along with him because it’s not what it was two years ago,” says Tom Davis, a former GOP representative from Northern Virginia and the former chair of the National Republican Congressional Committee. “You’ve had people leave the party and people come in, and it’s all around him. This is not the same Republican Party.”

Trump-style views on immigration and race dominate among both the party’s elected officials and its electoral coalition. While several of Trump’s rivals for the GOP nomination in 2016 questioned the value of his proposed border wall, very few Republicans in Congress now openly oppose it. Even when Trump advanced his wall with an unprecedented step—declaring a national emergency after Congress explicitly refused to provide him funding—just 12 Republicans in the Senate and 13 in the House voted to stop him. Similarly, a significant majority of both House and Senate Republicans last year voted for Trump-supported legislation to impose the largest cuts in legal immigration since the 1920s. (That bill didn’t pass, but on Wednesday, Republican Senators Tom Cotton of Arkansas, David Perdue of Georgia, and Josh Hawley of Missouri reintroduced legislation to cut legal immigration in half.)

Among elected Republicans, opposition to Trump’s immigration policies has “fragmented and collapsed,” says Douglas Rivlin, the communications director for America’s Voice, an immigrant-advocacy group that has typically pursued bipartisan legislative coalitions. “If you think immigrants are welcome in our country, you are not welcome in the Republican Party—that seems to be the bottom line.”

One reason resistance has eroded is that congressional Republicans have largely retreated to the parts of America least touched by immigration, and often least affected by diversity. Democrats already hold 31 of the 40 Senate seats in the 20 states where the foreign-born share of the population is highest. In 2020, Democrats have a strong chance to capture two more of the seats on that list—in Colorado and Arizona—and are pursuing competitive, though more uphill, opportunities in two others, Georgia and Texas. After sweeping losses in diverse suburban and urban districts in November, Republicans now hold fewer than one in five of the House seats where the minority population exceeds the national average, and fewer than one in eight of the seats in districts with more immigrants than average. Those numbers could fall further: The most concentrated grouping of Democratic House targets for 2020 is in Texas, where half a dozen House Republicans survived close races last fall in mostly diverse suburban districts.

All of this means that the voices that might most object to Trump’s direction are no longer in the room when Republicans caucus. “Part of the problem is the members who used to do that, or need to do that, they are not around anymore,” says Davis, who’s now a partner at the Washington, D.C., law firm Holland & Knight. “Most of the members you thought would speak up for this, because of their own political advantage, they are gone.”

But the Republican acquiescence to Trump also reflects the larger reality that the party is now relying on an electoral base preponderantly tilted toward the white voters most hostile to immigration and most uneasy about demographic change overall—what I’ve called “the coalition of restoration.” Those attitudes, with only a few exceptions, are dominant not only among the white Republicans without a college degree who comprise Trump’s base, but also among the college-educated Republicans who have expressed more qualms about other aspects of Trump’s behavior.

Recent polling on both specific policy choices and broader assessments of America’s changing demography capture the extent to which both the blue- and white-collar wings of the GOP have coalesced around insular views.

For instance, last year, not only did 76 percent of white Republicans without a college degree support building Trump’s border wall, but so did 71 percent of white Republicans with a degree, according to detailed results provided to me by Quinnipiac University. (Meanwhile, nearly three-fifths of the country overall opposed the wall.) In that same poll, nearly three-fifths of non-college-educated white Republicans and just under half of those with a degree supported Trump’s policy of separating parents from their children at the border. (Two-thirds of the country overall opposed it.) There was more daylight between the groups this March when Quinnipiac asked whether they supported Trump’s emergency declaration; but even so, the president’s move drew support from three-fourths of white non-college-educated Republicans and nearly three-fifths of those with a degree. (Two-thirds of all Americans opposed the declaration.)

White-collar and blue-collar Republicans also converge on questions measuring more fundamental attitudes about race relations and demographic change. Polling by the nonpartisan Pew Research Center released last month found that 66 percent of white non-college-educated Republicans and 61 percent of white college-educated Republicans believe that the U.S. becoming a majority-minority country will “weaken American customs and values,” according to numbers Pew gave me. (Americans overall split evenly on that question.)

New Pew polling released Tuesday similarly found that more than three-fourths of both college-educated and non-college-educated white Republicans believe that “people seeing discrimination where it does not really exist” is a greater problem than “people not seeing racial discrimination where it really does exist,” according to results given to me by Pew. (Nearly three-fifths of all Americans say the greater problem is people not seeing actual discrimination.) About three-fourths of both Republican groups said that the country today pays too much attention to race. (Just two-fifths of all Americans agreed.) Just one in six of non-college-educated white Republicans and one in eight of those with a degree said the country has not done enough to give black Americans equal rights with white Americans. (That compares with nearly half of all Americans.)

The most conspicuous exception to this anti-diversity tilt is that a majority of Republicans, in most polls, oppose mass deportation of undocumented immigrants already in the country, though by notably less decisive margins than do other Americans.

But by and large, the GOP is now overwhelmingly centered, both demographically and geographically, on the parts of America most uneasy about the nation’s changing face. “This is 20 years in the making,” Davis says. “The party has been doing this pre-Trump, but he put the exclamation point on it. It’s not the same party. I’ve told folks, ‘This is the party. And you are not going to change it.’”

The ongoing DHS purge suggests that Trump is likely to test the GOP’s tolerance for hard-line immigration policies through at least 2020. Among the ideas the White House has floated recently: offering undocumented parents a veritable “Sophie’s choice” of indefinite detention with their children or separation that would allow the children to seek asylum in the U.S.; an executive order to end birthright citizenship; expanded deportations of undocumented immigrants already in America; and accelerated efforts to construct the border wall. Which of these policies Trump will actually pursue, if any, remains uncertain. But the fact that he’s looking for someone “tougher” than Nielsen, who executed and then alternately defended and denied the existence of the family-separation policy, suggests that Trump and his close adviser Stephen Miller are committed to pushing the boundaries of both public opinion and the law. Trump has sent the same message with his openly xenophobic declarations in recent days that “our country is full.”

The aggressive ideas Trump has floated, as Davis notes, would likely energize his core supporters. But they would face intense opposition from core Democratic groups—especially minorities—and would likely repel many of the suburban white-collar whites that broke so decisively away from the Republican Party in 2018. An agenda of unbridled hostility to asylum seekers and both legal and undocumented immigrants also risks further alienating the GOP from the diverse Millennial and post-Millennial generations, many of whom already think that Trump is racist.

And yet, even as Trump inks this tattoo on the GOP, the will to resist him in the party has almost completely crumbled. Republican senators this week lavishly praised Nielsen for her work, without complaint about family separations or the other hard-line policies that defined her tenure. Even Nielsen offered only praise for Trump’s immigration agenda after her dismissal. “It’s hard to imagine there is traction for a pro-immigrant Republican to really define themselves within the party and chart a way forward,” Rivlin says. The border wall, symbolizing hostility to racial change, is now the electoral foundation of a Republican Party that Trump has remade in his image.

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