Russia and Belarus launched their largest joint military exercises ever on Thursday, a day after six Russian warships arrived in Crimea for naval drills that Ukraine says will paralyze commercial shipping in the Black Sea.
Why it matters: U.S. officials believe that Russia may use the exercises inside Belarus as cover to attack Ukraine from the north. Ukraine's foreign minister slammed the Black Sea maneuvers as "unprecedented" and a tactic of Russia's "hybrid war" designed to blockade Ukraine's southern ports.
