A firm grasp on reality. Photo: Chip Somodevilla/Getty Images

After spending Christmas Day not-at-all-sadly liking his old tweets, President Trump was back on the warpath Tuesday morning, attacking the FBI and claiming, for the second time in a week, that Obamacare is over.

Based on the fact that the very unfair and unpopular Individual Mandate has been terminated as part of our Tax Cut Bill, which essentially Repeals (over time) ObamaCare, the Democrats & Republicans will eventually come together and develop a great new HealthCare plan! — Donald J. Trump (@realDonaldTrump) December 26, 2017

As perhaps goes without saying, excising the individual mandate does not actually repeal the Affordable Care Act, though it may significantly damage it. The Congressional Budget Office projects that the move will leave about 13 million more people without coverage by 2027, but the actual effect of sawing one leg off of the fabled three-legged Obamacare stool will be complicated, and it will take years to assess the damage. (Also, the penalty for going without insurance will still be in place for one more year.)

Perhaps the more interesting point here is that, after Republicans failed several times to get rid of the law they hate so much, Trump has convinced himself, with the help of a dose of medical-grade delusion, that they have finally succeeded. This is despite the fact that core elements of Obamacare — Medicaid expansion, the individual marketplaces — remain intact, and that the law has become increasingly popular.

Trump’s blinkered view could actually be good news for Democrats. So far, the prospect of reviving Obamacare repeal efforts in 2018 has drawn a mixed reception from congressional Republicans; Senate Majority Leader Mitch McConnell showed little enthusiasm in doing so last week, then recalibrated his opinion after pushback from repeal champions like Lindsey Graham. But if President Trump considers the Affordable Care Act “repealed,” it may slow congressional momentum to do more harm until the next big test for the eternally embattled law: the 2018 midterms.