Russian and Western leaders don't see eye-to-eye on the crisis in Ukraine, but they've reached consensus on another important issue: Adolf Hitler was bad.

For European and American observers, Russia's annexation of Crimea echoes the Nazi leader's foreign policy between the military reoccupation of the Rhineland in 1936 and the seizure of the Czech Sudetenland in 1938. Garry Kasparov, the Russian chess grandmaster and prominent critic of Russian President Vladimir Putin, wrote as the Crimean crisis unfolded that between hosting the Olympics and invading neighboring countries, "[if] Putin wanted to do a better imitation of Adolf Hitler circa 1936-1938, he would have to grow a little mustache." Earlier this month, as Putin justified his moves in Crimea as an effort to protect ethnic Russians, former U.S. Secretary of State Hillary Clinton said, "Now if this sounds familiar, it's what Hitler did back in the '30s."

Examples abound of Hitler's pre-war aggression, and diplomats have compared Putin's actions to just about all of them. Polish Foreign Minister Radoslaw Sikorski called Russia's seizure of Crimea an "anschluss," evoking Hitler's 1938 annexation of Austria. A former Czech foreign minister, whose country was carved up by Germany after the Munich Conference of 1938, said Putin was "acting on the same principles" as Hitler did then. When Canadian Foreign Minister John Baird was asked if he meant to compare Russia's actions to Nazi Germany's invasion of the Sudetenland, he replied, "When you have one country invading one of its neighbors, using this type of outrageous and ludicrous rhetoric, it's hard not to."

In Ukraine, such criticism is aimed directly at Putin himself. "World War II began with the annexation by Nazi Germany of other countries' territories," warned Oleksandr Turchynov, Ukraine's interim president. "Today, Putin is following the example of 20th-century fascists." Others are even less diplomatic. "Do you have success negotiating with a killer?" wondered Ukrainian legislator Lesya Orobets when discussing diplomatic efforts with Putin. "Do you negotiate with Hitler?"...