Why is Putin doing this? Because he can. That’s it, that’s all you need to know. The situation in Kiev—in which people representing one half of the country (the Ukrainian-speaking west) took power to some extent at the expense of the Russian-speaking east—created the perfect opportunity for Moscow to divide and conquer. As soon as the revolution in Kiev happened, there was an unhappy rumbling in the Crimea, which has a large Russian population and is home to the Russian Black Sea Fleet. It was a small rumbling, but just big enough for Russia to exploit. And when such an opportunity presents itself, one would be foolish not to take it, especially if one’s name is Vladimir Putin.

Zdroj:  Putin Declares War on Ukraine. The Why and What Next | New Republic.