These days, some U.S. subs come equipped with sophisticated antennas that can be used to intercept and manipulate other people's communications traffic, particularly on weak or unencrypted networks.
"We've gone where our targets have gone" - that is to say, online, said Stewart Baker, the National Security Agency's former general counsel, in an interview. "Only the most security-conscious now are completely cut off from the Internet." Cyberattacks are also much easier to carry out than to defend against, he said.
One of America's premier hacker subs, the USS Annapolis, is hooked into a much wider U.S. spying net that was disclosed as part of the 2013 Edward Snowden leaks, according to Adam Weinstein and William Arkin, writing last year for Gawker's intelligence and national security blog, Phase Zero. A leaked slide showed that in a typical week, the Navy performs hundreds of so-called "computer network exploitations," many of which are likely the result of submarine-based hacking.
"Annapolis and its sisters are the infiltrators of the new new of cyber warfare," wrote Arkin and Weinstein, "getting close to whatever enemy - inside their defensive zones - to jam and emit and spoof and hack. They do this through mast-mounted antennas and collection systems atop the conning tower, some of them one-of-a-kind devices made for hard to reach or specific targets, all of them black boxes of future war."
But even this doesn't compare to what the Navy wants to be able to do next: turn its submarines into motherships for underwater drones that can maneuver themselves even closer to shore and conduct jamming or hacking operations while allowing the sub to work at a distance... [as a "mothership" see the heavily modified USS Jimmy Carter]
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