September 1, 1939. Seventy years ago, the Second World War began in Europe. German troops crossed the Polish border. German airplanes bombed fleeing civilians. This unprovoked attack prompted Britain and France—after an agonizing delay—to keep their commitment to Poland and declare war on Hitler.

The former Soviet Union, under Josef Stalin’s brutal rule, had cleared the way for Hitler’s invasion just one week earlier by signing the Nazi-Soviet Non-Aggression Pact. That devils’ bargain allowed Stalin to invade Poland from the East and to gobble up the tiny Baltic republics. When Hitler two years later tore up that pact and invaded the USSR, Stalin accepted Churchill’s generous offer of help. “If Hitler invaded hell,” Churchill humorously said at that grim time, “I would at least make favorable reference to the devil in the House of Commons.”

When World War II ended in Europe, Stalin’s Red Army commanded the eastern half of the continent. He sneered at any idea that Poland might yet be free. “How many divisions does the Pope have,” he asked with contempt. Soon an Iron Curtain, memorably described by Churchill in 1946 descended across Europe.

Only with the largely peaceful revolution of 1989 did that scar pass away. Only with the inspired leadership of Ronald Reagan, Margaret Thatcher, Lech Walesa, and Pope John Paul the Great did Eastern Europe throw off forty-four years of communist tyranny.

While Americans have been distracted by health care debates, the Russians have not been quiet. Vladimir Putin’s state-run television ran a long documentary arguing that Stalin had been right to make the bargain with Hitler. It justified the invasion of Poland and the grabbing of the Baltic republics. Most Russians today, according to the respected historian of the Gulag, Anne Applebaum, have no idea that the USSR invaded Poland in 1939. That’s how thoroughly Soviet history has been airbrushed in today’s Russia. It’s a tactic Stalin employed to great effect.

Vladimir Putin was recently “dissed” by President Obama on his first trip to Moscow. Secretary of State Hillary Clinton famously called for a “re-set” button to describe our relations with Russia—and then couldn’t find a correctly spelled button. And Vice President Joe Biden dismissed Russia as a declining power.

Meanwhile, Putin has brought back the Stalin-era national anthem. He’s restored a statue of “Iron Felix” Dzerzhinsky—the founder of the dreaded Cheka and forerunner of the KGB. And he’s not even talking about burying the heavily embalmed body of Vladimir Lenin in Red Square.

They say nature abhors a vacuum. So does history. Miss Applebaum notes that U.S. planners today “have no special reason to take Central Europeans seriously and increasingly don’t mind demonstrating the fact.” We are in danger of repealing Reagan’s greatest achievement. Hundreds of millions of people in eastern and central Europe owe their freedom to Reagan’s inspired leadership in the eighties. Today, seventy years after the war that brought death and despotism to this vast region, their freedoms are increasingly threatened.