There are myriad reasons why most Republicans, for whom Obamacare-repeal was once a signature issue, are running from it.

Voters overwhelmingly identified health care as the most important issue in last year’s midterm elections: 41 percent so named it, and the second most important issue, immigration, scored only 23 percent in exit polls. And Democrats, who campaigned heavily on it, won 75 percent of voters who saw it as the top issue. That helped carry Democrats to the largest midterm victory margin in history.

And, it turns out that Americans like having protections for people with pre-existing conditions. They like having insurance coverage: An Urban Institute study released this month found that 20 million people would lose their health care if the Affordable Care Act were repealed. And they like Obamacare. According to the Kaiser Family Foundation’s tracking poll, 50 percent of U.S. adults favor the 2010 health care reform law while 39 percent view it unfavorably.

Contrast that with Trump’s own upside-down job approval: A little under 44 percent approved of the job he’s doing as of Friday morning, according to the RealClearPolitics polling average, while nearly 52 percent disapprove.

Obamacare is vastly more popular than Trump. No wonder he hates it.

Thus, the Justice Department’s announcement Monday that, in a reversal of course, it supports a lawsuit aiming to completely invalidate the Affordable Care Act is a microcosm of Trump’s curious political instincts.

It is part and parcel with his clockwork-like impulse to follow up good news with self-conflagration: Trump had gotten a gift on Sunday in the form of his attorney general’s interpolation of Special Counsel Robert Mueller’s final report. Veteran Trump-watchers thus knew that a magnificently self-destructive victory tour was in the offing.

And, sure enough, then came the renewal of the unpopular GOP war on Obamacare (which even many congressional Republicans no longer want), a plan on which Trump doubled-down Wednesday. “We’re not talking about health care right now, but I will,” Trump told reporters, vowing to lead his troops back up a hill upon which they’ve already died repeatedly.

Many of Trump’s top lieutenants reportedly argued against re-entering this political meat-grinder: Two key cabinet members, Secretary of Health and Human Services Alex Azar and Attorney General William Barr, whose department will get stuck with the blame, opposed the move. California Rep. Kevin McCarthy, the House Republican leader and a reliable Trump ally, told the president point-blank that going after Obamacare was a bad idea. Senate Majority Leader Mitch McConnell said on Thursday that he was going to pass on re-engaging this fight. “I look forward to seeing what the president... can work out with” Speaker Nancy Pelosi, he told Politico. And according to The New York Times, even the normally sycophantic Vice President Mike Pence “was worried about the political ramifications of moving ahead without a strategy or a plan to handle the millions who could be left suddenly uninsured if the suit succeeded.”

Trump’s determination to pick this loser of a fight illustrates another aspect of Trump the politician: His mystifying inability or unwillingness to accommodate the broad public mood. He has repeatedly demonstrated a drive to appease his base at the expense of broader popularity. Solidly 75 percent of Republicans, after all, oppose Obamacare, per Kaiser. They no doubt thrill at the idea of litigating this issue yet again. (So do Democrats given that almost everyone else on their side.)

Health care is the second major issue from the 2018 elections upon which Trump is doubling down in the face of unmistakable voter unhappiness. He already did his best to make immigration the central issue of that campaign and, to the extent he succeeded, it hurt his party; one leading Republican pollster concluded that his relentless flogging of the issue cost the GOP the House. But having been scorched by voters on immigration, Trump nonetheless pursued the unpopular path of declaring a national emergency in order to build his (also unpopular) wall.

It’s almost as if the guy with authoritarian tendencies who won despite the will of the electorate doesn’t care about what voters want.

It seems that the only effort he’ll bother to make to appeal to those outside of his own base involves ludicrous sweeping vows. During the 2016 campaign he promised “insurance for everybody” in his Obamacare replacement, a pledge more akin to the Democrats’ “Medicare for all” than anything the GOP would seriously entertain. Now it’s that “the Republican Party will soon be known as the party of health care,” as Trump declared Tuesday. It’s an assertion that even left Republicans befuddled, because the truth is that, before they can own the issue, Trump and the GOP have to coalesce behind an actual replacement for Obamacare — preferably one which has popular support.

But an alternative to Obamacare has been a conservative bugaboo since even before Obamacare passed. As former Republican National Committee spokesman Doug Heye tweeted Wednesday, “Having worked (wholly unsuccessfully!) on Obamacare replacement in 2014, I’ve seen up close how Republicans can’t agree on much of anything re healthcare. To move anything, Trump Admin will have to go all in, long-term. Doesn’t seem terribly likely.”

Indeed, no one thinks the famously policy-details-averse Trump – he of the short attention span who once declared his surprise at the complexity of health care – has morphed into a wonk capable of threading the policy needle.

All of this is of a piece with Trump’s apparent 2020 re-election strategy: Find issues that wind up the base in an effort to reassemble his winning coalition from 2016. Never mind that that victory was rested on an 80,000-vote margin in Wisconsin, Michigan and Pennsylvania, or that, if Trump gets his way, according to the Urban Institute, the ranks of the uninsured would rise by 153,000 people in Wisconsin (a 35 percent increase), 720,000 in Michigan (115 percent) and 858,000 in Pennsylvania (133 percent). Oh and in Texas, the state which by itself provided Trump with his Electoral College margin of victory, people would see its uninsured rolls rise by 1.7 million (37 percent).

And that brings us to arguably the most troubling thing about Trump the politician: He’s president. And, as such even when he’s ineptly pursuing an unpopular agenda, he can still blunder into inflicting real damage on Americans.