AP Photo

Sunday marks the 70th anniversary of the Molotov-Ribbentrop Pact, a nonaggression treaty between the two totalitarian powers of the Soviet Union and Nazi Germany, as well as a secret protocol that divided Eastern Europe into spheres of influence between Adolf Hitler and Josef Stalin.

In May, President Dmitry Medvedev authorized a commission to investigate cases of historical revisionism of World War II to the detriment of Russia. The move followed the approval a year earlier of new school textbooks that reassessed the role of Stalin, acknowledging that he had made some errors but noting in turn his achievements and successes, particularly in the war years. Taken together, they symbolize the new Russian policy of identifying contemporary Russia with the former Soviet...