Last week, the U.S. Senate voted in solidarity with Ukraine and other democracies threatened by authoritarian tyranny. Eighty years after the U.S. and Allied armies liberated Nazi-occupied Europe in World War II, history is again challenging freedom-loving nations. What will history write of this new conflict between democracies and authoritarians? Will history be as kind this time to the Allies, whose World War II victory over the Nazis ushered in both the greatest period of peace and progress Europe had ever seen and unbridled prosperity for America? The pages of 21st century history are being written now in Ukraine. It...