Russian President Vladimir Putin delivers a speech during a ceremony in Moscow on June 1. (Kirill Kudryavtsev/Agence France-Presse via Getty Images)

IN WINSTON Churchill’s famous “Sinews of Peace” address at Westminster College in Fulton, Mo., on March 5, 1946, he warned of “two gaunt marauders” stalking the world, “war and tyranny.” He declared that “an iron curtain” had descended upon Europe and insisted that “we must never cease to proclaim in fearless tones the great principles of freedom and the rights of man. . . .” He described free speech, democracy and rule of law as the “title deeds of freedom” and implored, “Let us preach what we practice — let us practice what we preach.”

These words, spoken in a different age, are worth recalling today as autocrats and tyrants are on the march. A different kind of curtain is descending, denying billions of people those basic “title deeds” of freedom. No longer is it about communism, but rather the rise of despots who rule by force and coercion, from Russia to China, across the Middle East and Central Asia, to Latin America and Africa. In the past decade, these leaders have become more adept — and daring — at building a parallel universe to the liberal democratic order. In their construct, state power reigns supreme, political competition is extinguished, civil society elbowed out, and freedoms of expression, association and belief suppressed.

Surprisingly, some of these leaders, particularly in Russia and China, have been wielding a sophisticated and deceptive soft power beyond their borders that is proving more enduring and effective than in the past. Their tactics are asymmetrical and subversive, using deception and disinformation, not easily confronted.

The United States and other democracies need a strategy to counter this new wave of authoritarianism, including with 21st-century versions of the soft-power weapons that worked for the West during the Cold War.

Just as the U.S.-sponsored radio stations beamed truth behind the Iron Curtain, the West today should build a powerful digital “transmitter” that can reach billions of people trapped in dictator-land. It should help people circumvent digital firewalls and take advantage of new social media. When hundreds of Chinese realized they’d been fleeced in a pyramid scheme recently, they found a way to leap the Great Firewall and organize on Twitter. Why? Because these tools work. They empower people and defy the heavy hand of the state.

A global democracy strategy must draw on more familiar tactics, too, including public diplomacy, selective pressure on authoritarian regimes and what Churchill called “fearless tones” of reproach. The West needs to contest more vigorously the battle for ideas, a struggle in which Russia and China have become adroit, flooding the international media space with toxic propaganda, from broadcast outlets such as Russia’s RT and China’s CCTV News to armies of Internet trolls. The West’s strategy cannot and should not mimic odious big-state propaganda. Rather, it should showcase liberal values and ideals.

The U.S. government in recent years has a poor track record in such attempts. In some quarters, the United States is a discredited exponent of democracy. But these are problems to be solved rather than reasons to avoid action. A new presidency is a good moment to develop and launch a strategy to defend democracy. Without it, freedom will continue to lose ground.