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The Russians are on the verge of dramatically expanding their previous invasion of Ukraine, this time with enough forces that they could roll through the streets of Kyiv. I will admit that when the Soviet Union collapsed 30 years ago, I did not expect that the new Russian Federation—poor, militarily weak, but finally free—could be, or would want to be, a threat to its neighbors. This was a failure of imagination on my part.

But about one thing I was certain, and remain so: It’s a good thing that Ukraine never became a nuclear-weapons state. Now that the Russians are poised to invade, this bad idea is coming around again. There are sensible people I respect who disagree about this, and so I think it’s worth a little time to consider that no matter how bad things might get, they would only be worse if Ukrainian nuclear weapons were involved.

A series of historical and political circumstances have brought us to this point, going all the way back to how the USSR was created in the first place. (There are reasons, for example, that the Ukrainian state exists in its current borders and for why Crimea ended up a bone of contention, but that’s a subject I’ll explain in an additional newsletter later this week.)

Today, let’s just ask a basic question: Would nuclear weapons have protected Ukraine now?

American “realists” like Professor John Mearsheimer, among others, think so. This is a simplistic answer, as realist answers so often are. It is a view of the world as something like a big game of Risk, in which all the countries are basically alike except for how many pretty colored chips they control. This approach leads foreign-policy analysts to say things that sound deep and logical, but make no sense when real countries, with real histories, governed by real people, get involved.

It also assumes that nuclear weapons are magical talismans that protect anyone who holds them.

They’re talismans, alright. Like a Monkey’s Paw.

Mearsheimer, for those unfamiliar with him, is the University of Chicago scholar who said back in 1990 that European stability might improve if Germany became an independent nuclear power. This is no slam on the Germans, but nobody—including the Germans—wanted that. He then said it about Ukraine in 1993 and 2014.

The reality here is that it was not in America’s interest, or anyone else’s, to have more nuclear states appearing out of nowhere in 1991. When the leaders of Russia, Ukraine, Belarus, and Kazakhstan signed the USSR into oblivion, they were also the four republics with Soviet nuclear weapons on their territory. None of them really had a clue about what to do with those weapons (or with the rest of the remnants of the Soviet military, for that matter). Mikhail Gorbachev, upon his resignation as head of the USSR, gave Boris Yeltsin all the launch codes, but the weapons were scattered all over the place.

The Americans were rightly worried about this, and the solution back in 1992 was something called “the Lisbon Protocol”—I know, this sounds like a Robert Ludlum novel—in which all four of these former Soviet “nuclear republics” agreed to become signatories to the Soviet-American START Treaty, recognize Russia as the Soviet nuclear successor state, transfer all Soviet nuclear weapons to Russia, and make disposing of them Moscow’s responsibility.

So far, so good. Now imagine that the Lisbon Protocol never happened.

Imagine instead that a nuclear-armed Ukraine and Russia then go through decades of instability and violence and corruption, including everything from Yeltsin’s tanks in Moscow in 1993 to the 2014 Maidan protests in Kyiv.

The likelihood is that the Ukrainian nukes, instead of being a security blanket, would have been a Russian pretext for war long before now. Even Yeltsin might have felt the need to move against them if things looked to be getting out of control in Kyiv. And the political environment has never been all that stable in Ukraine, for a lot of reasons too long to go into here. The reality is that through the 1990s and 2000s, Ukraine failed to curb problems of corruption, of Russian influence in its intelligence services, and of basic economic instability.

The old-school realists think Putin would never have dared invade a nuclear-armed Ukraine, but I think that’s just projecting American academic biases onto a foreign country. After all, the United States damn near charged into World War III over Soviet nuclear weapons in Cuba in 1962. Does anyone think that Russian leaders and their military high command were going to live with former Soviet nuclear weapons—their own weapons—pointed at them on their borders?

This is where the realists become obtuse: We Americans might have gone to war, they admit, because the balance of power demands it, but the Russians would never have done such a thing. Why not? Because reasons, or something, but mostly because realism doesn’t make a whole lot of sense (which is also a post for another time).

The more likely scenario, in my view, is that a Ukrainian nuclear stockpile would have been low-hanging fruit for any Russian government, and especially for a desperate Kremlin that might have wanted to whip up an instant crisis, real or imagined, over “Ukrainian nuclear stability.” Instead of treading carefully, Putin and his goons might have presented the U.S. and NATO with claims that the Ukrainian chain of command was breaking down or that terrorists or proliferators were making inroads into the nuclear stockpile. (Some of those charges might even have had some substance back then; the Ukrainians didn’t have the codes to operate the weapons, which would have made it tempting to sell them in pieces to wealthy bad guys.)

The Kremlin would then have argued that letting Ukraine keep its nukes was a dangerous mistake. Other nations might well have agreed. Who knows, even America might have agreed, because many of those weapons were targeted at the United States.

Now imagine the progress of any such crisis between Ukraine and Russia. Ukraine, as a defensive measure, increases its military and nuclear readiness (or says it does, as much as possible, even without the codes). The Kremlin, giving Washington the “we told you so” look, then raises Russian nuclear-alert status as both a precaution and a warning. The Europeans, facing a potential holocaust on the Continent that everyone had managed to avoid for 50 years, declare a pox on everyone’s houses, but especially on Ukraine’s house. The Americans then raise their alert status because…well, because that’s what you do in a crisis.

Anything could happen at that point.

I imagine you might have questions. Perhaps one of them is: “What the hell? Why didn’t we do anything to head this off? Didn’t we sign something to prevent all this?”

Well, yes. Sort of. In 1994, Russia, the U.S., and the United Kingdom signed the “Budapest Memorandum.” (I know, another great Ludlum title.) This agreement required that Ukraine—and Belarus and Kazakhstan in identical agreements—give up nuclear weapons, but affirmed that everyone would respect Ukrainian territorial integrity, refrain from military action, abjure the use of nuclear weapons against the non-nuclear states, and consult the UN Security Council in the event of armed aggression.

That’s it.

A very different Russia signed that memorandum, but in the end, all the Budapest Memo could do was to express the hope that the United Nations would step in if things ever got a bit too sporty. It was not designed to deal with a Kremlin gang led by a diminutive and clean-shaven version of Saddam Hussein practically declaring that Ukraine is the 19th province of Russia.

I know there are those who argue that North Korea and its successful dash for nuclear status is the object lesson here, but that’s the wrong lesson. The North Korean regime has long been saved by geography rather than nuclear arms. For one thing, almost every scenario for war in Korea begins with the unavoidable destruction of Seoul, only 30 miles from the border. And things would get worse from there; even Richard Nixon, who wanted a plan in 1969 for a nuclear strike on the DPRK, backed off when he realized it simply wasn’t possible without raising hell far beyond any benefit that would come from wiping out the North Korean military.

Look, this situation is bad. It’s very bad. But adding nuclear weapons to the mix would make it worse, and probably would have resulted in a major war—a war over nuclear weapons—15 or 20 years ago. Sometimes, there are no good solutions in foreign policy, only gradations of terrible.

This is one of those times.