AFTER the WAR: IN THE AFTERMATH OF RUSSIA'S INVASION OF UKRAINE, IT'S TIME FOR EUROPE TO STEP UP AND AMERICA TO STEP BACK.

• Author: Welch, Matt

DRAMATIC ACTS OF aggression from a big country against outgunned independents defending their own turf can shock the world's conscience and trigger fundamental changes to the international order. The Soviet-engineered communist coup in Czechoslovakia in 1948 and subsequent military blockade of West Berlin led directly to the creation in 1949 of NATO. The 1956 joint invasion of Egypt by the U.K. and France (with an assist from Israel) permanently discredited European colonialism, hastening that foul institution's already rapid demise. Iraq's forcible annexation of Kuwait in 1990 prompted George Bush and Mikhail Gorbachev to jointly declare that "no peaceful international order is possible if larger states can devour their smaller neighbors," a principle they said would be woven into an emerging "new world order." That order turned out great for the Kuwaiti monarchy, whose rule was restored after a U.S.-led, 39-country coalition drove Saddam Hussein's soldiers back into Iraq. But for the rest of the Middle East and North Africa, and even within pockets of comparatively stable Europe, the hoped-for settlement following the end of the Cold War has proven disappointingly disorderly--a missed opportunity to design fresh new international institutions around the imperial withdrawal of both superpowers and the concomitant reassertion of responsible self-governance across the rapidly expanding free world.

Russia's illegal, unprovoked, and unconscionably brutal assault on its former imperial holding of Ukraine has, within its first month, precipitated head-snapping changes to existing geopolitical realities. Germany kiboshed a long-planned Russian gas pipeline and significantly increased its defense budget overnight. Long-neutral Finland and Sweden started making noises about joining NATO. More refugees were displaced from their homes in a matter of weeks than in all the 1990s Balkan wars combined. Moscow's armies and armaments, while unforgiving on civilian populations, were revealed to be far less potent against actual combatants than virtually anyone predicted, scrambling conventional strategic calculations. European Union leaders fast-tracked Ukraine for membership, and for the first time agreed to take seriously France's longstanding proposal to create a meaningful defense alliance separate from the United States.

That Washington was largely a bystander to these developments is neither accident nor trifle. Compared to even three decades ago, the countries on the continent that once produced the world's most cataclysmic wars are in considerably stronger position to prevent new ones from metastasizing. The resolve of their response suggests a once-in-a-generation opportunity to retool the global order, especially America's role in it, to make Putinesque acts of aggression more costly and less likely.

President Joe Biden, as unsuited as he may look for the task, has a chance to finally wrap a bow on the Cold War, helping both America and the world become more secure by making the last remaining superpower less responsible for the world's security. It's a counterintuitive approach, one that does not fit easily into the parochial and self-centered way foreign policy is usually discussed within American politics. But events have made the improbable possible, lending urgency to a long-term rethink that may yet offer Ukrainians a short-term path toward the existential certainty they have so valiantly earned. The end of this war can, with some bold and agile statecraft, become a hinge point--not just for lasting Ukrainian independence, but for the cause of global peace.

THE POLITICS OF POSTWAR

"AT LAST," PRESIDENT Woodrow Wilson enthused at a luncheon in Portland, Oregon, in September 1919, "the world knows America as the savior of the world!" That boast would prove premature.

Three times in the 20th century, the United States emerged at the end of a bloody and exhausting global conflict more powerful and less damaged than long-dominant European powers. Washington in each case was in prime position to shape the stuff of postwar settlement--the redrawing of borders, exchange of populations, payment of reparations, resizing and redeployment of troop levels, establishment of new security guarantees, and creation of new transnational institutions to effect these changes and resolve future disputes.

The first time, America's ambitious and naive aspirations largely (though not completely) fell short; the second time, there was literally no other country remotely prepared to shoulder the burdens of European reconstruction and global containment of imperial communism. The third cessation of conflict was, as we shall see, a zig-zaggy, loose-ended mess, with no domestic or allied political consensus about how international relations might be rearranged.

All three postwar settlements provide us with usable lessons, not least of which is the importance of public opinion on U.S. commitments to overseas entanglements.

Washington in 1918 was a newcomer to great-power status, a latecomer to the war, and brimming with new ideas about how to avoid old problems. Wilson held enough leverage after World War I to extract support among the eye-rolling European allies (England, France, Italy) for his idealistic goals of abolishing secret treaties, carving out nation-states for the long-subjugated peoples of Central and Eastern Europe, and launching his dream project, the League of Nations. But the Democratic president never could...