Mr. Zelensky’s decision to remain in the capital, Kyiv, while it’s under Russian attack — and his family’s decision to stay in Ukraine — has moved many, particularly in contrast to the Afghan president, Ashraf Ghani, who fled Kabul as soon as the Taliban were on the outskirts, demoralizing what was left of the Afghan army.

He and his team have also made excellent use of social media, with impassioned speeches showing his presence on the streets of Kyiv going viral. Ordinary Ukrainians are reporting on events in Ukraine on TikTok, and some people are making videos hailing Mr. Zelensky and showing Ukrainians doing what they can to push back Russians — filling bottles meant for Molotov cocktails, volunteering to fight, being issued with automatic weapons and vowing to defend their country…

But Mr. Zelensky has also inspired European leaders to do more for Ukraine. Appearing onscreen during the emergency summit meeting of European Union leaders three days ago, on Feb. 24, he gave a passionate 10-minute speech that moved some reluctant leaders to endorse a harsher package of economic sanctions on Russia, a senior European official said.

His intervention will be part of history, said the official, who was in the room. It was very emotional, leaders were deeply affected.