AFL-CIO President Richard Trumka speaks at the 2016 Democratic National Convention.Scott Audette / Reuters

From his very first words, AFL-CIO President Richard Trumka snapped heads across the Democratic coalition when he appeared on Fox Business Network last week to assess President Trump’s first speech to Congress.

“I think it was probably one of his finest moments,” Trumka told host Maria Bartiromo. Over the next five minutes, Trumka criticized some aspects of Trump’s agenda. But mostly he stressed his agreement with the new president on issues such as trade and immigration.

With his surprisingly warm appraisal, Trumka—who also met privately with Trump on Tuesday—captured how the administration’s disruptive agenda is accelerating the class inversion reshaping American politics. Both on cultural and economic grounds, Trump’s brusque, racially tinged economic nationalism is generating unusually broad resistance for a Republican president among college-educated voters of all races. But that same message continues to demonstrate enormous appeal for working-class whites. And although there’s little evidence of it yet, Trump’s aides hope his “America First” agenda will eventually attract blue-collar African Americans and Hispanics, too.

Even without those inroads, the cresting wave of white blue-collar support for Trump last November already carried him deeply into union ranks. In 2012, Barack Obama beat Mitt Romney among households that included a union member by 18 percentage points. Trump cut that margin exactly in half, losing to Hillary Clinton by just nine points among all union households. Among whites in union households, Trump beat Clinton by 12 points, exit polls found. Among whites without a college degree in union households, Trump crushed Clinton by 26 percentage points.

That history seemed to sit heavily on Trumka’s shoulders during his Fox interview. He denounced elements of the agenda that Trump and congressional Republicans are advancing, such as their plans to cut corporate taxes and weaken Wall Street regulations.

But on trade, he praised the president for promising to reopen the North American Free Trade Agreement and abandoning President Obama’s proposed free-trade zone across Asia, the Trans-Pacific Partnership. On immigration, Trumka said he was “actually pleasantly surprised to hear him say that the system is broken and it’s legal immigration as well as undocumented people. … This is the first time you heard the president talk about legal immigration being used to drive down wages. We’ve been saying that for a long time.”

While many Democrats view Trump’s browbeating of individual companies to invest more in the United States as something between symbolism and a shell game, Trumka vouched for its value. “You can look at the jobs he didn’t save,” he said, “or you can say if he saved one job by speaking out, to that one family, that’s the most important thing in their lives.” Likewise, while many Democratic strategists believe that an appeal to racial resentment was central to Trump’s victory, Trumka readily agreed with Bartiromo that the president won because voters felt left behind economically.

In other words, even with the occasional jab at the president, Trumka’s interview offered plenty of clips that presidential adviser Stephen Bannon would be happy to insert into Trump 2020 commercials in Ohio, Michigan, and Pennsylvania.

In an interview, AFL-CIO spokesman Josh Goldstein walked back one point from Trumka’s remarks. During last week’s speech, Trump proposed tilting future admissions of legal immigrants toward a “merit-based system” that favors skilled workers and deemphasizing family reunification, which he suggested imports too many unskilled people. Goldstein said the AFL-CIO opposes reorienting legal immigration in that way; Trumka’s remarks to Fox praising Trump’s immigration language, he said, referred to the program that imports high-skilled workers on temporary visas. Trump has criticized that program at other points, but did not mention it in his speech.

Even with that qualification, a high-ranking labor official, who closely watches the federation’s politics, said that Trumka’s sunny interview reflects a larger reality: While labor can unify to fight Trump on issues that directly affect its core interests, it is unlikely to denounce him as systematically as other cornerstone Democratic groups. On Tuesday, the AFL-CIO reflected that uneasy balance by issuing a pointed statement condemning the House Republican bill to replace Obamacare and a bland second statement on Trumka’s White House meeting that neither praised nor criticized Trump.

Behind the hesitation is a fundamental split between the craft, building trade, and industrial unions where Trump generated significant support, and the service, teacher, and public-employee unions where he’s anathema. “The nature of how diverse the labor movement is would make the resistance posture untenable,” the labor official said. “There are unions where 50 percent [of the members] voted for him. Those unions have to pay attention to that, and the federation has a very difficult job of straddling that and the unions where 70 percent voted for Clinton.”

President Richard Nixon famously promoted affirmative-action programs for construction projects partly to split the Democratic coalition by pitting organized labor against African Americans. The unions could soon face another such wedge: While the AFL-CIO has opposed Trump’s plan to build a wall at the U.S.-Mexico border, it has not moved to pressure unions to boycott the project. Participating in construction would infuriate Hispanic leaders, including those within labor’s ranks, but as journalist Harold Meyerson has observed, a boycott would trigger opposition from building trade unions where Trump ran well. “Building the wall is a ticking time bomb,” the labor official said, “because either way it’s a big deal.”

Just as in the overall electorate, the blue-collar whites most drawn to Trump are shrinking within organized labor as it grows more racially diverse. Unless Trump succeeds in attracting skeptical working-class blacks and Hispanics, Trumka will face increasing pressure to more firmly oppose the president. But forcing unions to hedge their bets on opposing Trump, even temporarily, can only increase the GOP’s odds of avoiding losses in 2018—and holding the White House in 2020.

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