AP Photo

Five years ago in the former Soviet Union, governments loyal to Moscow were falling roughly every six months. Those were the glory days of the "color revolutions" that brought new leaders to Georgia, Ukraine and Kyrgyzstan in quick succession between 2003 and 2005, all with the backing of the United States. The region's political center of gravity was tilting sharply toward the West. But now that trend has been reversed. In the past three months, two of those governments have been ousted. Leaders far friendlier to Russia have again taken power in Ukraine and Kyrgyzstan, displacing the Orange and...