In one of the strange rhymes that history favours, nearly eight years after Mr Barack Obama's Democrats managed the extraordinary feat of losing a Senate race in Massachusetts, Mr Donald Trump's Republicans have matched the feat by losing a Senate seat in Alabama.
Mr Roy Moore and Ms Martha Coakley don't really have a lot in common personally, but their respective defeats have one essential similarity. They are both stark repudiations of a first-term president, foreshadowing a larger repudiation soon to come.
What was repudiated in Massachusetts in early 2010 was a specific policy course: the Obama White House's pursuit of a sweeping and complex healthcare Bill in the teeth of an enormous recession, which unsettled voters who wanted hope and change only so long as the latter didn't affect their health insurance premiums.
The fact that Ms Coakley was a terrible candidate made it easier for Mr Scott Brown to torpedo her, but the backlash against Obamacare, the feeling that a liberal president had turned too soon from seeking growth to seeking redistribution, was an essential element in her defeat.
There is an unpopular Republican tax Bill now to echo the unpopular Democratic healthcare Bill eight years ago, but policy is a much smaller part of what was repudiated in Alabama. It was not so much a rejection of the Trump agenda as it was a rejection of the whole Trumpian mode of politics, which since his election has consisted of a trebling down on the most unattractive features of his campaign style.
Mr Roy Moore, in this sense, was Mr Trump's Trump . The President has harassment accusations; the judge had mall-trawling accusations. Mr Trump is a race-baiter; Mr Moore was a stock character from a message movie about Southern bigotry. And like Mr Trump but much, much more so, the Moore campaign relied on the assumption that Republicans who didn't care for who he was and what he represented simply had nowhere else to go.
So while Mr Moore's defeat is, yes, specific to him, specific to the statutory rape accusations and all the rest of his problems as a candidate, it's also a pretty clear foretaste of what you get when you distil white identity politics to a nasty essence and then try to build a coalition around it.
You get massive Democratic turnout, black turnout in particular, slumping Republican turnout, and a whole lot of write-in votes from people who should be your supporters. You get Democrats winning elections in unlikely places. And you get, quite probably, a Democratic majority in the House and perhaps even the Senate.
Is that future inevitable? In theory, no. When Mr Brown won in Massachusetts, it was possible to imagine the Obama White House learning something from the defeat, course-correcting on healthcare, making a public show of being chastened.
They did not do so, in the end, but they certainly considered it, with Mr Rahm Emanuel in particular championing that course - one that might, might, have saved some Democratic House and Senate seats in the Republican wave of 2010.
So just as the Obama people considered course-correcting after Ms Coakley's loss, you could theoretically imagine the Trump people course-correcting after Mr Moore's - inducing the President to abandon his online feuds and insults, weaving a little more racial sensitivity into his rhetoric and actions, even persuading the GOP leadership to rewrite its tax Bill to make it a little less howlingly unpopular.
But who are we kidding? The Obama White House considered a course correction because, for all its flaws, it was a rational and functional place, capable of doing cost-benefit analyses and changing strategies as the political situation altered. And Team Obama decided to stay the course for what were debatable but also rational reasons - the theory that a sweeping healthcare Bill would be simply worth the political pain and midterm election losses required to get it passed.
No such rationality exists in the Trump White House. You can't change course without a map; you can't change your plan when you don't have one to begin with.
Maybe we'll get a new and "presidential" Mr Trump for a few days or even a couple of weeks after this debacle. But none of it should be taken seriously. Mr Trump can control himself for a short time here and there, but tomorrow is always another day. And Twitter is always waiting.
No, there will be no course correction - only the Trump we've seen so far, the Trump who would rather have the GOP fall in ruins around him than give up on his feuds and insults and absurd behaviour, the Trump who made Senator Doug Jones our strange reality, and the Trump who is also responsible for the larger wave that's building, building, for next fall.