Some 80 years ago, on Aug. 23, 1939, Nazi Germany and the Soviet Union signed the Molotov-Ribbentrop Pact, formally known as the “Treaty of non-aggression between Germany and the Union of Soviet Socialist Republics.”
The world was shocked — and terrified — by the agreement. Western democracies of the 1930s had counted on the huge resources of Communist Russia, and its hostility to the Nazis, to serve as a brake on Adolf Hitler’s Western ambitions. Great Britain and the other Western European democracies had assumed that the Nazis would never invade them as long as a hostile Soviet Union threatened the German rear.
The incompatibility between communism and Nazism was considered by all to be existential — and permanent. That mutual hatred explained why dictators Adolf Hitler and Josef Stalin both despised and feared each other.
Yet all at once, such illusions vanished with signing of the pact. Just seven days later, on Sept. 1, 1939, Germany invaded Poland. World War II had begun.
After quickly absorbing most of Eastern Europe by either coercion or alliance, Hitler was convinced that he now had a safe rear. So he turned west in spring 1940