No one wants a U.S.-Russia shooting war, and Mr. Blinken makes an important point that a no-fly zone could require NATO pilots engaging with Russian planes. For that and other reasons we’ve said a no-fly zone would be hard to implement and might divide NATO.

But why tell Mr. Putin that he has nothing to fear no matter what he does in Ukraine? If he had some doubt about greater military assistance to Ukraine, the Russian might not be so willing to bomb cities with indiscriminate artillery and cluster bombs.

Mr. Blinken also led with weakness on possible sanctions on Russian oil and gas exports. “The immediate effect would be to raise prices at the pump for Americans and also to pad Russian profits with rising prices,” Mr. Blinken said. The latter point isn’t true if Russian exports plunged, and the former point tells Mr. Putin the West fears the political risk at home from rising gasoline prices more than it wants to deny financing for Mr. Putin’s war.