I’ll keep this brief because there’s only so much gloom we can shoulder before the holidays, but anyone who pays attention to foreign policy—you, me, NATO, folks like that—are all wondering if Russian president Vladimir Putin is going to use the huge military force he’s building up along the border with Ukraine.

Will Russia attack? Could it all turn into World War III, an all-out conflict between Putin’s diseased regime and the 30 nations of the Atlantic Alliance?

These are two separate questions. A Russian attack on Ukraine is possible and even probable; we know this because it’s happened before and the current “peace” along the border is merely an unstable cease-fire. World War III, however, is a lot less likely, and the use of nuclear weapons is even less likely.

But none of this is impossible.

There are plenty of solid pieces out there about why Putin might attack Ukraine yet again, and so I won’t go through that exercise here. You should be reading, if you’re not already, people like former U.S. ambassadors Mike McFaul and Steven Pifer and Russian dissident Garry Kasparov. They know, as do most Russia-watchers, that the key to understanding Russia’s intentions lies not in old-school theories about “realism” and “geopolitics,” but in the nature of the Mafia running the Kremlin.

Putin, like every autocrat, knows that democracy anywhere is a threat to his own regime, because people making their own decisions and running their own lives gives his own citizens some unhealthy ideas. And when it’s being practiced by former Soviet subjects—and especially by other Slavs—right on his doorstep, he gets especially itchy. As McFaul put it smartly and succinctly, Putin is not threatened by NATO expansion into Ukraine but by the existence of democracy in Ukraine.

Putin is dealing with this threat by warning Ukrainians that their independence exists only at his sufferance. And so he might try to remind everyone in Kyiv, Washington, and Brussels that he’s in charge by using a blitzkrieg military victory to force a quick collapse of the Ukrainian government.

This is what it would look like: Russian forces storm over the border, overwhelming tired and under-supplied Ukrainian forces. Local militias join in the effort. This is a repeat of Crimea and the 2014 invasion of eastern Ukraine. (As an aside, let me just note here that Ukrainians thought it would be a hoot in 2019 to replace their last president with an actual comedian named Volodymyr Zelensky, who is now completely in over his head. Elections have consequences.)

Casualties mount on both sides, but Putin squelches any critical reporting and ugly video inside Russia, while the Ukrainian government has its losses plastered over all the international press and the internet. Western governments wring their hands, free Ukrainians demand action from Kyiv, and pro-Putin legislators and public figures in Ukraine point fingers at Zelensky.

Out of options, with the morgues filling up and his military in retreat, Zelensky resigns or is hounded out of office. Putin, via “advisors” and stooges on the scene in Kyiv, then oversees a panicked effort by some caretaker regime to find a suitably pro-Kremlin leader.

This would be a huge gamble on Putin’s part. The Ukrainians might not have the most efficient government in the world, but I wouldn’t want to wade into a fight with the Ukrainian people. They’re not pushovers, and a lightning war might not work. And the Russians—especially younger Russians—don’t really want to have to fight a protracted and bloody struggle with people about whom they actually care very much.

But you can see where some sort of cockamamie Russian version of Operation Ukrainian Freedom would appeal to Putin. The United States and NATO would have to stand by helplessly while Russian troops bolt across the border and Kyiv falls into chaos. If all goes well for Vladimir Vladimirovich, Ukraine becomes a Russian satrapy, the West looks like a collection of feckless talking heads, and the Russian people celebrate the greatest leader since Peter the Great. (Or, at least, since Putin’s old boss Yuri Andropov.)

But does it become a world war, and does it go nuclear?

I doubt it. Ukraine is not a NATO nation, and no foreign powers have an actual obligation to defend its territory. If you’re thinking of the 1994 “Budapest Memorandum,” let that go. That was not a military guarantee but a piece of paper in which pre-Putin Russia, the U.S., and the United Kingdom agreed to respect Ukraine’s borders.

But that doesn’t mean you shouldn’t worry. War is not only hell, it’s unpredictable. The two things I worry about are “black swan” events—the kind of freak accident you cannot imagine until it happens—and the even stranger problem that all-out war becomes more likely if the Russians lose.

I can’t tell you what a black swan would look like; that’s the nature of a black-swan event. Perhaps aircraft from neighboring NATO nations are shot down by Russians. (This happened in Syria.) Perhaps a rogue operation, or a provocation meant to be “deniable” by the Russians, gets out of hand. (This also happened in Syria.)

Putting thousands of troops in motion is a roll of the dice, even when the odds are with you. (Any blackjack player who’s doubled down an 11 against a six and ended up staring at the dealer who turned over a five and dropped a paint knows the feeling.) Clausewitz called this “friction”: the million tiny things that can make even a well-planned operation go wrong. Putin isn’t stupid, but he’s not a genius, either. He’s been lucky up until now. Saddam Hussein had the same kind of luck for years, right up until he was pulled from a spider hole.

The difference is that Putin has nuclear weapons. I doubt anyone in Moscow or in Washington is going to let things in Ukraine go nuclear, but if the Russians are getting their asses kicked by Ukrainians using Western-supplied weapons, you can count on it that Putin and his military chiefs will engage in dark reminders that Russia has a nuclear arsenal.

The actual path to nuclear use is less clear—unless NATO forces get involved, which would be a game-changer. If fighting somehow broke out between NATO and the Russian Federation—a contest Russia would, sooner or later, lose—then yes, the Russians could go to a heightened state of nuclear alert, which means we would go to a heightened state of nuclear alert, and then we all stare intensely at the technical means that warn of us things like indications of a nuclear launch and…well, I mentioned black swans, didn’t I?

But NATO isn’t going to do that; in fact, I suspect NATO is now wishing it hadn’t committed to the idea of Ukraine joining NATO in 2008. And so I don’t think any of this is likely to turn into a major East-West conflict. If Putin doesn’t “shock and awe” the regime in Kyiv into collapse, he’ll settle for a simmering and continual bloodletting on the border that he will keep out of the Russian media for as long as he can.

Sort of like his mentors did in Afghanistan. And that didn’t work out so well for them.

I’m sorry to talk about this so close to the holidays. In fact, one of my readers, Carmen D., recently asked me why I’d write about World War III so close to Christmas. (I believe her exact words were: “Aaack.”)

That’s a fair point, Carmen, so in a few days, I’ll send you all another newsletter, with more of your mail, and a discussion of Christmas music. I’ve already slagged your beloved Christmas television viewing; why should I spare the music?

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