Thank heaven for ... alabama?

Good riddance to Roy Moore and the horse he rode in on.

If I sound jubilant, you bet I am. And if I’m being snarky, well, Moore of all people warrants it. He actually arrived at the polls Tuesday on a steed named Sassy. What an endearing adjective for an awful man.

In short order I’ll talk about the political implications of his surprising, jolting defeat by Doug Jones in Alabama, the first time in more than a quarter-century that voters in this deep-red state elected a Democrat to the U.S. Senate.

But those can’t be divorced from the soaring emotions of his win. What it does for the spirits of people petrified by his country’s trajectory can’t be overstated.

For more than a year now, virtually all Democrats, many independents and even a significant share of Republicans have looked at President Donald Trump’s conduct and governing priorities and felt that they were suddenly in a foreign land. I count myself among this stunned and despairing group.

We saw decency in retreat. We saw common sense in decline. We saw a clique of unabashed plutocrats, Trump foremost among them, brazenly treating the federal government as a branding opportunity or a trough at which they could gorge. We saw a potent strain of authoritarianism jousting with the rule of law.

And we saw many Americans, including most Republican leaders, either endorsing or quietly putting up with this, to a point where we wondered if some corner had been turned forever.

That’s still an open question. But Alabamians provided a partial answer on Tuesday, showing that there are limits to what voters will tolerate, in terms of the lies they’ll believe, the vices they’ll ignore and the distance they’ll stray from civilized norms.

Moore, an accused child molester who sugarcoated slavery and seemed intent on some sort of extreme Christian theocracy, was simply too far.

With his defeat comes relief, yes, but also a desperately needed encouragement.

Trump openly supported Moore, urging the residents of a state that he won by about 30 points in November 2016 to reward him anew and smile again on the GOP. Their refusal to do so is vivid proof of the president’s vulnerability, no matter Moore’s flaws. If Trump can be foiled here, he can be foiled elsewhere.

Democrats began this year in a state of panic and confusion, their party diminished almost unimaginably over the course of Barack Obama’s presidency. Republicans hold both chambers of Congress. They control many more state governments than Democrats do.

And though they gave their presidential nomination to a ludicrous and offensive candidate — an amoral showman — they won the White House nonetheless.

But now, as Trump completes a crazily turbulent first year in office, Democrats are on a streak — or certainly feel that way. Last month, the party’s candidate handily won the governor’s race in Virginia, where heavy Democratic turnout translated into huge gains for Democrats in the state legislature.

Alabama adds to that, and it’s a different story altogether, a state in which the Republican candidate in recent gubernatorial and Senate elections has typically prevailed by a whopping double-digit margin similar to the one that Trump achieved.

Alabama amplifies Democrats’ sense of momentum going into the 2018 midterms, which, on the evidence of what happened Tuesday, could be a blood bath for Republicans.

Historical patterns already boded ill for the GOP; the Alabama results are a brutal harbinger on top of that. I happened to speak midday Tuesday with one of the smartest Republican strategists I know, and he predicted a Republican comeuppance in 2018 so profound that it could alter the party forever or even jeopardize its survival.

And about this: Trump, a man amply unbalanced, is being thrown further off stride and out of whack. In Alabama’s Republican primary in September, he followed the advice of the party’s Congressional leaders, backed Luther Strange over Moore, perceived Moore’s victory as an embarrassment and blamed those leaders for subjecting him to it.

Then he got behind Moore even as some of those leaders refused to, and now this. He’s certain to deem them culpable for stymying Moore and to rage at them, if only to divert attention from how ineffectual his blessing of Moore turned out to be. Either that or he’ll start hallucinating voter fraud.

Apart from their tortured relationship with Trump, Republican leaders caught a break here. While their Senate majority now shrinks to one vote, they won’t have to welcome a senator who’s another stain on a party that can’t bear any more of them.

But Democrats are the bigger victors. Scratch that: Americans are. If Alabama isn’t beyond redemption, then the country isn’t, either. To use a word that Moore would appreciate: hallelujah.