It may not happen today. It may not happen tommorrow. But someday, Russia's annexation of Crimea will take a bite out of its massive energy industry. With over 50% of the federal budget coming from oil and gas revenues and multibillion-dollar agreements with big oil players ExxonMobil (XOM -0.57%), BP (BP -0.94%), and Total (TTE -0.44%), it is very possible this deal could severely hurt the Kremlin's pocketbook more than it realizes.

The trouble facing Russia's energy industry will probably not come from economic sanctions; Russia's contributions to the global oil and gas market are simply too much to make up from other places. However, aggression like this will very likely cause its largest customer, the European continent, to reduce its reliance on Russian exports though other investments. Find out how else this could affect Russia and even the future prospects of these big oil players by tuning into the video below.