Eric Gay / AP

HOUSTON—Overhead, the little red plane with the white stripe went around and around, circling and droning, circling and droning—impossible to ignore, pointless to pay attention to. It was a stunt, and by this mention alone, the Trump campaign may feel it got a return on its investment, reportedly $7,500. SOCIALISM WILL KILL HOUSTON’S ECONOMY! VOTE TRUMP 2020 read the big blue banner trailing the plane, for anyone who looked up.

Down below last night, the 10 leading Democratic presidential candidates were onstage arguing over the details of their grand plans for health insurance, gun control, and combatting climate change—justifying and explaining their proposals in a way the president has rarely done.

In presidential-primary debates, Republicans are typically asked what they’re going to do. Democrats are asked that too—plus questions about how they’re going to do it. There’s a small-c conservative sensibility underlying that approach from many in the political media, an assumption that the country doesn’t want or isn’t prepared to handle significant change, because Congress hasn’t made that change already—despite what favorable public polling may suggest about some of the Democrats’ biggest proposals. Reporters often adopt the voice of a hypothetical centrist voter who’s inherently skeptical of just how far to the left the Democratic Party has moved. This mentality drives professional Democrats nuts: “I always say, the status quo is the strongest lobbyist in D.C.,” Representative Ruben Gallego of Arizona, who was in town to endorse and promote Senator Kamala Harris of California, told me after the debate.

But the candidates might as well get used to it. As long as Senator Mitch McConnell of Kentucky is running the Senate, major Democratic proposals are going nowhere; his power as majority leader—and a filibuster rule that requires 60 votes for most legislation—makes the chances of success unlikely. As the 2020 primary cranked up to its next level of seriousness with the third debate last night, so did that big question for the Democrats onstage: How exactly are they going to do what they’ve proposed?

Most of the candidates said they were eager for a detailed discussion. Yet none were ready to embrace the challenge entirely. Senator Elizabeth Warren of Massachusetts, for example, tried to avoid directly answering a question about whether middle-class taxes would go up under Medicare for All—even though Senator Bernie Sanders of Vermont, whose plan she’s endorsed, acknowledges they would. (He’s argued that Americans would save money overall on their health-care costs.) And Warren has still never quite explained how she proposes to pass the 2 percent wealth tax that is at the core of her candidacy. Meanwhile, the moderators wanted to know, what is Joe Biden’s plan to counter China’s economic rise if not the Trans-Pacific Partnership, a trade deal he once helped sell but now opposes? How would Sanders get any of his major proposals through the Senate when he still supports keeping the filibuster in place? How would former Representative Beto O’Rourke of Texas build support in Congress for mandatory assault-rifle buybacks? The answers largely remain mysteries.

Eventually the how can catch up to politicians. Consider Republicans’ “repeal and replace” pledge. For years, GOP leaders promised to release a health-care plan that managed to retain all the popular elements of the Affordable Care Act. House Republicans voted dozens of times to roll back the ACA, with Democrats in the Senate ultimately blocking their efforts. In 2017, a repeal push in the upper chamber only failed because of the late Senator John McCain of Arizona and his famous thumbs-down. Yet at no point has a full replacement plan emerged, even as Donald Trump has promised that he’s not done trying to get rid of Obamacare.

Some of the candidates last night rejected getting in the weeds, preferring to campaign in clear, bold swings. “Frankly, I think this discussion has given the American public a headache. What they want to know is that they’re going to have health care and cost will not be a barrier to getting it,” Harris said at one point, trying to short-circuit a long exchange on health care. “This reminds everybody of what they cannot stand about Washington: scoring points against each other, poking at each other, and telling each other that—my plan, your plan,” South Bend, Indiana, Mayor Pete Buttigieg said a few minutes later, trying to muscle into an exchange between Biden and former Housing Secretary Julián Castro. “Yeah, that’s called the Democratic-primary election, Pete,” Castro fired back. “That’s called an election.”

“I think it makes sense, asking how you’re going to get it done,” Castro told me afterward. “Democrats tend to be a little more introspective about how you’re actually going to do things. On the whole, I think that that’s good.” At the first debate, Castro drew attention with his proposal to make crossing the American border illegally a civil charge instead of a criminal one. I asked him whether he worries that getting too deep into detail could backfire on Democrats. He told me that was a great question, and he’d have to think about it.

“There’s a fundamental difference between Republicans and Democrats: Republicans talk about all the things they’re going to kill and not do, so it’s easy to not do things. How much detail do you need for that?” Jeff Weaver, a senior adviser to Sanders’s campaign, told me in the spin room. “Democrats, to varying degrees, are talking about doing new and different things, so that requires explaining.”

“The expectation is that Trump’s going to do nothing, and for Democrats, the biased expectation is ‘You can’t get it done,’ so it starts with a negative,” echoes Brad Woodhouse, a veteran Democratic operative who’s now the executive director of the Obamacare advocacy group Protect Our Care.

Needless to say, the level of detail in a proposal doesn’t always correspond to its seriousness. Just look at Trump. Remember how Mexico was going to pay for the border wall? In the spring of 2016, after much pestering from the press, his campaign produced a two-page memo, a rare dive for the campaign into actual specifics (though it’s barely anything compared with most of the plans 2020 Democrats have released). The memo described how Trump would squeeze the money from Mexico overnight through transaction fees on remittances sent by people in the United States and through raising the price of visas. The administration never pursued that approach once Trump won the presidency, and these days, it’s pulling money for the wall out of military bases.

“Republicans get a pass on a whole lot,” said Massachusetts Attorney General Maura Healey, who was walking around the spin room as a surrogate for Warren, her home-state senator. I asked Healey why she thinks that’s so. “If I had the answer to that question,” she said, “I’d do something about it.”

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