KIEV, Ukraine — To Viktor Yushchenko, the man at the heart of Ukraine’s Orange Revolution a decade ago, March 2014 looks a lot like August 1939. Europe, once again, is at war. But Europe is also, once again, refusing to realize it and react. Yushchenko, the former Ukrainian president who has spent much of his political life at odds with Russian President Vladimir Putin, and incurred his wrath, says there should not be any doubt about what is going on: Putin’s Russia has been waging economic and information war on his country for years. It has now added a territorial...