The World, Moved, Needs to Move Cautiously in Ukraine We admire Zelensky and want to help his country. But escalation poses threats far beyond its borders.

It is good to be moved. It feels good to admire without ambivalence. The West is united, suddenly and surprisingly, and that feels good too.

Volodymyr Zelensky stirred the world not only by what he said but what he did. He has put it all on the line, including his life. Early on he told the press the intelligence services had informed him he is Russian target No. 1, his wife and two children target No. 2, but they’re staying, they won’t leave. It is reminiscent of the summer of 1940 and London bracing for the blitz. Prime Minister Winston Churchill, asked if the children of the British royal family, Princesses Elizabeth and Margaret, shouldn’t be sent to safety overseas. This was the answer of Queen Elizabeth, wife of King George VI: “The children could not go without me, I could not possibly leave the king, and the king would never go.” So they stayed. Princess Elizabeth has been queen now for 70 years.

Ukrainian President Volodymyr Zelensky speaks in Kyiv
Ukrainian President Volodymyr Zelensky speaks in Kyiv

To move the world as Mr. Zelensky has, to become a David figure, an international icon of liberty and guts, is more than a human achievement, it is a true strategic fact of the conflict. If two weeks ago he had fled for London and were now making spirited Zoom speeches to his countrymen back home, would Ukraine have stood and fought as it has? He gambled his courage would be contagious, and could be leveraged.

Things are certain to become more full of feeling as the war shifts into a sustained phase of brutality. Civilian populations targeted, hospitals and apartment buildings shelled, the dead buried in trenches, food shortages, more than two million refugees, a number that will grow far higher if they can get out, though Russia seems less interested now in letting them out than leaving them trapped. All this in the first real-time war, being delivered moment by moment to your phone. People think the gruesome pictures function as helpful propaganda for Ukraine, but in time they will function as well as propaganda for Vladimir Putin: You think I’m losing? Look at your winners, digging mass graves.

Talk of providing Mr. Putin a face-saving “off-ramp” strikes me as absurd. He doesn’t want an off-ramp; he wants to stay on the highway, and Russian diplomats aren’t acting as if they’ve lost face or even been embarrassed. Central Intelligence Agency Director William Burns is surely right: On Tuesday he told the House Intelligence Committee that Mr. Putin will likely “double down and try to grind down the Ukrainian military with no regard for civilian casualties.” He’s going for the rubble.

And yet. The West must try with everything it has to end this. Cease-fires, talks, negotiations that become serious, possible compromises, efforts at “deconfliction”—every attempt has to be made and made again. That’s what diplomats exist to do, find a way out when history turns hard.

Here is where the figure of Mr. Zelensky and all he means, all his power to move and persuade, can become a different kind of factor. His great and primary mission is to save his country. That is his job and his purpose. It isn’t, and probably can’t be in human terms, seeing to the broader security and safety of “the world.” He is simultaneously running a government, commanding its military, addressing his people to keep up their morale, and talking to the world to stoke its support. All while being bombed.

To put it crudely, it isn’t bad for his purposes if the war escalates, as long as escalation means more allies giving Ukraine what it needs. He won’t mind broadening the conflict if it protects Ukraine. It is his allies who have to worry about broadening the conflict.

On Wednesday Mr. Zelensky tweeted a video of a bombed maternity hospital in Mariupol. He called it an “atrocity,” asked how much longer the world will be an accomplice. He has beseeched the West for a no-fly zone: “Close the sky right now!” It would be a blunder to give him what he asks for. A no-fly zone enforced by the U.S. or the North Atlantic Treaty Organization would inevitably entail direct engagement with the Russian military. Since the dawn of the nuclear age the U.S. has carefully avoided direct hostilities with the world’s second-biggest nuclear power. If the war in Ukraine escalated in this way, Mr. Putin could use it to justify the use of terrible weapons, not only nuclear or cyber but also biological or chemical.

So while we are being moved by Mr. Zelensky, we must keep all these questions in mind. Mr. Putin has stated that if he is impeded in Ukraine the world will be shocked by his response. At the beginning of the war he put his nation’s nuclear forces on high alert. Director of National Intelligence Avril Haines told House Intelligence that Moscow hasn’t made such a pronouncement since the 1960s.

Mr. Putin’s threats can be understood as a bluff or as a clear and factual warning of intent. It’s possible he himself doesn’t know how far and how low he’d go. But I’m struck by the assertion of the justly confident Fiona Hill, the diplomat and Putin scholar, in an interview with Politico last week: “The thing about Putin is, if he has an instrument, he wants to use it.”

Obviously if Mr. Putin decided at some point to use a battlefield tactical nuclear weapon, it would be a catastrophe for the world. But it’s even more than that. What must be said is that once something like that starts, it doesn’t stop. The taboo is broken. It is extremely important for the world that the taboo not be broken. Once a nuclear weapon is used, the use of nuclear weapons is “on the table” in human history—a possibility, another move open to leaders when a war begins. And we can’t let that happen in a world full of monsters who’d use such weapons in a shot but so far haven’t quite felt permitted to break the taboo and usher in a new, dark age.

Even in times of high Western passion—the Soviet suppression of Hungary in 1956 and Czechoslovakia in 1968, the invasion of Afghanistan in 1979, and during the brilliant Polish freedom movement called Solidarity in the 1980s—America maintained a spirit of responsive restraint, of judicious engagement, that got us through without missiles flying. We don’t know that “stick with what worked” guarantees anything now, but that it worked in the past is its own encouragement.

We must do what we can without sparks flying, and Lord knows we should be talking to Russia about Ukraine’s 15 nuclear reactors. It’s not only a matter of “don’t hit them,” it is that human beings have to work there to keep them safely operating—showing up each day during a war, sustaining their professionalism, not being unnerved and making mistakes while they’re being shelled.

The West must feel what it feels and not let it compromise our judgment. You probably know this without someone saying it, but I’m getting the impression not everybody does.