What are Russian submarines up to?

David E. Sanger and Eric Schmitt report in the New York Times,

Russian submarines and spy ships are aggressively operating near the vital undersea cables that carry almost all global Internet communications, raising concerns among some American military and intelligence officials that the Russians might be planning to attack those lines in times of tension or conflict.

The issue goes beyond old Cold War worries that the Russians would tap into the cables — a task American intelligence agencies also mastered decades ago. The alarm today is deeper: The ultimate Russian hack on the United States could involve severing the fiber-optic cables at some of their hardest-to-access locations to halt the instant communications on which the West’s governments, economies and citizens have grown dependent.

While there is no evidence yet of any cable cutting, the concern is part of a growing wariness among senior American and allied military and intelligence officials over the accelerated activity by the Russian armed forces around the globe. At the same time, the internal debate in Washington illustrates how the United States is increasingly viewing every Russian move through a lens of deep distrust, reminiscent of the Cold War.

...Adm. James Stavridis, formerly NATO’s top military commander and now dean of the Fletcher School of Law and Diplomacy, said in an email last week that “this is yet another example of a highly assertive and aggressive regime seemingly reaching backwards for the tools of the Cold War, albeit with a high degree of technical improvement.”

...What worries Pentagon planners most is that the Russians appear to be looking at vulnerabilities at much greater depths, where the cables are hard to monitor and breaks are hard to find and repair.

...So important are undersea cables that the Department of Homeland Security lists their landing areas — mostly around New York, Miami and Los Angeles — at the top of its list of “critical infrastructure.”

Attention to underwater cables is not new. In October 1971, the American submarine Halibut entered the Sea of Okhotsk north of Japan, found a telecommunications cable used by Soviet nuclear forces, and succeeded in tapping its secrets. The mission, code-named Ivy Bells, was so secret that a vast majority of the submarine’s sailors had no idea what they had accomplished. The success led to a concealed world of cable-tapping.

And a decade ago, the United States Navy launched the submarine Jimmy Carter, which intelligence analysts say is able to tap undersea cables and eavesdrop on communications flowing through them.

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