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…

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.”