In recent weeks, Donald Trump has again broached a once-unthinkable topic. No, not tariffs on allies or extorting white shoe law firms or threatening a federal takeover of Harvard University. More jarring, from the perspective of Republicans on Capitol Hill, has been the president’s argument for raising taxes on the wealthy. Trump floated the idea recently in a meeting with top Senate Republicans, ostensibly as a way to offset other, more populist tax cuts he promised on the campaign trail, like no tax on tips. Republicans, of course, are under enormous pressure to cover the multitrillion-dollar cost of extending Trump’s 2017 tax cuts. Most have been studying ways to cut at least $1 trillion of federal spending (or more, or less, depending on which Republican you ask). Only a small minority of Republicans support the idea of raising taxes on high-income earners, which is anathema to everything the party has long professed to stand for. But stranger things have happened than lawmakers getting comfortable with a policy they once reviled. Ever since their meeting with the president, Senate Republicans have been feverishly discussing the details of how raising taxes on the top 1 percent could work. The ideas that have been floated include raising the top tax rate from 37 percent to 39.6 percent—the rate during the Obama years—for those making more than $609,000 per year, and creating a new, slightly higher tax bracket for those making more than $1 million. Potential supporters of the plan suggest that a 2 percent increase on the highest earners would barely be felt. Republicans have also discussed closing the loopholes for carried interest and dividends, I’m told, though they have been truly sacred cows. Some populist-oriented Republicans and deficit hawks are open to the idea, and some have even argued for it. Both Rep. Andy Harris, the chair of the hardline Freedom Caucus, and Senator Josh Hawley, for instance, have said they’re in this camp. Supporters note that letting tax rates rise for the wealthy could help offset the cost of extending Trump’s other tax cuts or blunt the need to pay for them. They could also help pay for other Trump tax priorities, such as no taxes on tips or Social Security. Raising taxes on the wealthy could raise hundreds of billions to more than a trillion dollars in revenue, depending on the policy. The right-leaning Manhattan Institute estimates that taxing capital gains and dividends at 39.6 percent would raise another $330 billion. House Speaker Mike Johnson has downplayed the idea, telling Fox News last weekend that he’s “not a big fan” of raising taxes on the wealthiest. But it was notable that he didn’t dismiss the possibility outright. After all, if Trump wants to go for it, Johnson is hardly going to torch their relationship to go to bat for billionaires. And Johnson has already capitulated repeatedly on issues that the party once considered sacrosanct, like standing up for free trade and projecting American power throughout the world. Raising taxes on the wealthy, then, would be just another Rubicon to cross—the latest step in Trump’s ongoing political realignment. “God put Republicans on planet Earth to cut taxes,” political strategist Brad Todd told me, quoting the late conservative columnist Robert Novak. President George H.W. Bush’s failure to uphold his “no new taxes” pledge helped make him a one-term president, and Republicans still sign Grover Norquist’s no tax-hikes pledge—six newly elected senators and 28 House members did so this year. It would be a “reality altering” paradigm shift if Republicans became the party of taxing the rich, Biden’s top economic advisor Jared Bernstein told me. “It used to be that Democrats tried to sound like Republicans on taxes to win voters. Now, Republicans are trying to sound like Democrats,” said Democratic strategist Jesse Ferguson.