For Russian President Vladimir Putin, the annexation of Crimea isn’t just a land grab; it’s an energy grab.

Indeed, it wasn’t long after rejoining the Russian Federation that the Crimean legislature voted to seize the oil and gas assets of several Ukrainian companies. Hydrocarbon reserves throughout the Black Sea have also been nationalized. It’s easy to understand why: the more energy resources Russia controls, the greater Putin’s political power — especially since Europe’s economy relies heavily on Russian oil and gas.