The U.S. Navy has formally reestablished its Second Fleet as a result of a renewed focus on the North Atlantic Ocean, where the Russian military has been operating with increasing frequency in a way not seen since the Cold War. . . .
The revived fleet reflects a major shift in U.S. military strategy recently from focusing on terrorism in the Middle East — where the Islamic State extremist group last year was largely defeated — to growing U.S. competition with both Russia and China.