Wars are won by deeds—but also by persuasive moral arguments.

“Deeds, not words,” is the motto of the 22nd Infantry Regiment, a credo that befits a fighting unit that has seen service from the Civil War to Iraq. But wars are won by words as well as deeds, which is one of the reasons President John F. Kennedy, quoting Edward Murrow, said that Winston Churchill “mobilized the English language and sent it into battle.” And now, in Ukraine, the United States and the West in general need much better words to put into the fight in addition to the long-range artillery and guided missiles, air-defense systems and drones, accurate artillery shells and bullets that they are shipping—belatedly, insufficiently, occasionally hesitantly—into battle.

President Volodymyr Zelensky, the most inspiring Western war leader since Churchill, knows the power of language. “I need ammunition, not a ride,” will make the history books. His speeches to Congress, the U.K. Parliament, and the Bundestag were outstanding examples of impassioned persuasive speech. But something more is needed from the president and prime ministers of his friends and allies.

The United States and its allies have had a remarkably, perhaps perilously easy time in persuading their people to go along with extensive aid to Ukraine, despite high inflation and energy shortages. To some extent, this is the result of the West’s muscle memory from the Cold War, when Soviet ideology was relentlessly hostile and Soviet internal practice stunningly brutal. Soviet external behavior, from the subjugation of the Baltic states and Eastern Europe to the invasion of Afghanistan, was menacing as well as repellent. And even though the Cold War is more than a generation behind us, when the Russians behave like brutes—“orcs,” as the Ukrainians refer to them—that muscle memory is triggered.

Americans are used to seeing the Russians as the bad guys, and thus our institutions, including the armed forces and the CIA and its foreign counterparts, have a deep repertoire of actions ready in response. The Russians launched an unprovoked war against Ukraine, committed atrocities on a massive scale, and have daily compounded their crimes by attacking civilian infrastructure abroad and brutalizing their own people at home. It is easy (and correct) to conclude that they remain the bad guys today. That we can see the bombed playgrounds and hospitals and the tortured bodies of their victims on Twitter makes it so much easier to mobilize against them.

The tests are coming, however, particularly if Europe has a cold winter that makes Russian cutoffs of energy supplies bite. In the United States, the likely next speaker of the House of Representatives, Kevin McCarthy, in a gesture to the neo-isolationist wing of the Republican Party, has indicated that it is time to curtail aid to Ukraine. The motley collection of so-called realists (who think that Russia’s crimes are irrelevant), isolationists, admirers or tools of Russia, and America-Firsters have kept up a running if muted line of criticism, not so much of the Zelensky government as of the American burden in supporting him.

McCarthy’s views have nothing to do with principle, because he has none. Rather, he is a weather vane, acutely sensitive to the winds that blow from Mar-a-Lago and the wing of his party that has always resented America’s presence in the outside world. The isolationist and even xenophobic traditions of one faction in the Republican Party run deep. Suppressing them for the past several generations was the great achievement of politicians like Dwight D. Eisenhower and intellectuals like William F. Buckley. But they are back and need to be addressed, as do comparable movements on the left of the Democratic Party.

Even more important, average Americans, properly worried about inflation, recession, and a bitterly divided political class, need to hear why it is important to weigh in, wholeheartedly and with vigor, on Kyiv’s side.

Two kinds of words are needed: those explaining why the fight for Ukraine is important to American security and welfare, and those making the case on moral grounds. No American policy can succeed in the long run without addressing both our interests and our values. When the two coincide, as they did during World War II and the Cold War, the United States can show remarkable perseverance. When they diverge or are weak, as became the case in America’s interventions in Afghanistan and the Middle East, policies collapse.

A good speech on Ukraine will not invoke the phrase “rules-based international order,” which might resonate in a freshman introduction to international relations, but not with an audience of normal people. Rather, Americans and Europeans need to hear about the consequences if Russia were to crush Ukraine; about the invasions and depredations that would surely come next in the Baltic states, and quite likely beyond; about the conclusions a no less ruthless Chinese government would draw; and about how a failure to take a stand here would mean something much bigger and more dangerous in a few years’ time. They need to hear how staunchness now, even in the face of nuclear threats, is infinitely better than a large-scale, possibly global war in a decade. They need to hear that world war is not just the stuff of history books or their grandparents’ or great-grandparents’ lives, but a possibility for us if we are not prudent now.

They also need to hear about the semi-genocidal nature of the Russian attack on Ukraine—not just the extensive torture, murder, and rape of the civilian population, but the kidnapping of thousands of children, and the attempt to wipe out Ukrainian language and culture.

Americans also need to hear a celebration not only of Ukrainian courage and tenacity, but of their skill. On January 20, 1940, Churchill gave a speech in which, among other things, he reflected on Finland’s astonishing early defeats of the Soviet armies that had attacked it a few months before.

Only Finland—superb, nay sublime—in the jaws of peril—Finland shows what free men can do.

And he issued a warning:

If the light of freedom which still burns so brightly in the frozen North should be finally quenched, it might well herald a return to the Dark Ages, when every vestige of human progress during two thousand years would be engulfed.

Now is a moment for Churchillian rhetoric and insight, suitably modified to the limitations of those who may share his instincts but lack his brilliance.

Modern politicians very rarely speak this way, but they need to try, and they will be heard if they do so. They do not have to reach Churchillian heights. The opposition to aid to Ukraine is still divided, hampered by its own crankiness and embittered introversion, and undermined daily by Russian barbarity, and no less, the astonishing Julius Streicher–like candor with which its propagandists howl for the blood of innocents.

Ukraine’s struggle for freedom and for its very existence is the struggle of a much larger order, not just in Europe but globally, and indeed of the human spirit. It needs to be understood not only in the somnolent rhythms of bureaucratic choice or academic analysis, but in language that sings. The situation calls for sound policy, no doubt; it also calls for eloquence that soars. There is an epic speech to be delivered here; let us hope that there is someone who can deliver it.