The health care law, said Thomas Miller, a fellow at the conservative American Enterprise Institute, has underscored how new entitlements inevitably become part of what he called the “demilitarized zone” of politics.
“One of the problems Republicans have had in 2017 is that the narrative and the discussion have changed,” Mr. Miller said.
“The territory could not be liberated — you could only contain its expansion,” he added. “Unlike a speculative law which had not been fully unloaded, put in place with money starting to flow, people have gotten checks, they’ve gotten benefits. It’s taking away from what’s already there.”
But it is not just the tenor of the debate that has changed. The bill that the House passed last week was less ambitious than the full-on repeal that conservatives have argued for since President Barack Obama signed the law seven years ago.
Conservatives had pushed Congress to pass a clean repeal bill in the first days of Mr. Trump’s presidency. They feared that the longer they waited, the more time Democrats would have to argue that Republicans wanted to callously rip benefits away from hard-working Americans.
“There’s a reason this has never been done before in the modern era,” said Tim Phillips, president of Americans for Prosperity. With new government benefits, he said, comes incredible political power.
“It builds constituencies, you have powerful special interests whose jobs suddenly depend on it, and the left fights intensely to protect government power once they’ve established it,” added Mr. Phillips, whose group, which is backed by the billionaire brothers David H. and Charles G. Koch, was one of the most ardent foes of the law from the moment Mr. Obama started pursuing it in 2009. “We knew then and we know now that this is not going to be easy.”
As politically useful as it may be to retain parts of the law, many conservatives have started asking whether the Republican Party is abandoning its core principles.
“If you can’t unbuild this structure, then what the hell are you doing here?” said William Voegeli, a senior editor at the Claremont Review of Books, a conservative journal.
Mr. Voegeli pointed to a long list of government programs that Republicans have promised to defund or eliminate — the National Endowment for the Arts, public broadcasting, the Department of Education and, of course, the Affordable Care Act — amid the expansion of the liberal “administrative state,” to use a term popular inside the Trump administration.
“You run on election cycle after election cycle with Republicans complaining but never taking the obvious next step,” he said. “And eventually you’re going to get a lot of restless conservatives out there.”
On Fox News over the weekend, the conservative columnist Charles Krauthammer said Republicans had basically given up on arguing for a more purely free-market health care system.
“They have sort of accepted the fact that the electorate sees health care as not just any commodity, like purchasing a steak or a car,” Mr. Krauthammer said. “It’s something now people have a sense the government ought to guarantee.”
The complexity of unraveling the Affordable Care Act became evident to Republicans even before Mr. Trump was sworn in, as they started planning their legislative agenda for his first 100 days. Led by Speaker Paul D. Ryan, the party assumed that a repeal would be one of the first items — if not the first — on its calendar.
Then Mr. Trump, who had campaigned on preserving programs, like Social Security, Medicare and Medicaid, that his party had aimed at in the past, said on Twitter less than two weeks before Inauguration Day that a replacement must accompany a repeal — much to the surprise of Mr. Ryan and the party leadership on Capitol Hill.
To the dismay of many conservatives, the promise to repeal had morphed into a pledge to replace. Even worse, some Republicans started talking about another dreaded R word: repair.
Mr. Ryan, speaking on Sunday on ABC News, used language not ordinarily heard from free-market, anti-entitlement conservatives like himself. The speaker, perhaps his party’s most vocal proponent of bringing down the cost of entitlements, argued for the House bill not on the basis of how much money it would save — in part because he rushed the vote before a proper accounting could be completed — but how many people would be left covered.
He called Republicans’ efforts a “rescue mission” to provide affordable health insurance, “especially and including to people with pre-existing conditions.”
The health and human services secretary, Tom Price, sounded a similar note, telling NBC News that the goal was something that Republicans usually dismissed as utopian fantasy: universal coverage.
“What we’re trying to do is to make certain that every single person has health coverage,” he said.
Even if the official party line is merely to provide access to coverage, the bill that the House passed aims to preserve some of the most popular parts of the 2010 law. For instance, Republicans say they have kept protections for people with health conditions that would have allowed insurers to deny them coverage before, though critics say they may face higher costs.
“They’re basically taking Obamacare and changing it around the margins,” said Adam Jentleson, a former senior aide to Harry Reid, who led Senate Democrats when the law was passed.
Also lost in the debate today is much of the disagreement over the proper scope of government authority. Republicans in the past often framed the debate in terms of personal freedom, choice and liberty — as opposed to the soft tyranny that can come through well-meaning laws.
“The debate over power and authority here is really a slugfest over who makes key decisions,” said Robert E. Moffit, a senior fellow at the Heritage Foundation, “and whether the key decisions in health care ultimately should end up in the hands of a government office or in the hands of individuals who are exercising free choice.”
Some saw another lesson for Republicans: that the general and philosophical are merely that.
“Republicans are strongest on these issues on the level of generality as opposed to the pragmatics,” Mr. Miller, of the American Enterprise Institute, said. That explains why their arguments have shifted to explaining how the law is failing rather than how it is a betrayal of the American tradition.
“What they were making was a consequential argument. It needed to be replaced because it wasn’t working, it wasn’t doing what people wanted,” he added, “as opposed to trying to say: ‘You know, we think this will work in a better way, but there are values at stake here. You need to be in control of your choices.’”