AP Photo

A storm is gathering in and around the Black Sea as Russia faces a mounting challenge from the United States, which is beefing up its military presence in former Soviet satellite countries like Romania, Bulgaria and Hungary. One look at a map of the region shows the critical geopolitical importance of the Black Sea, as its southern coast connects to the Middle East via Turkey and its northern coast adjoins Ukraine, which is home to Russia's Black Sea Fleet and which houses 80 percent of the pipelines supplying natural gas from Russia to Western Europe.