Russian submarine threat has U.S. Navy scrambling to respond

The Ohio-class ballistic-missile submarine USS Pennsylvania (SSBN 735)

Russia’s increasingly active submarine fleets in the Atlantic and Arctic have the Trump administration scrambling to respond, amid fears that miles of underwater fiber-optic cables that crisscross the ocean floor transmitting Pentagon’s most sensitive military secrets could be at risk. But with an aging submarine fleet and growing threats from North Korea and elsewhere, the Navy’s…