Oddly enough....the October of the US Naval Institute (USNI) monthly magazine cover is dedicated to "Submarines and Undersea Warfare" with articles about Defense and Repair of Undersea Cables (which should also now include pipelines as well) and other Submarine topics relevant to US Navy Submarines.
Several issues in the past year have dealt with US Naval Strategy, Tactics, Logistics, and Resources in ships, subs, aircraft, and personnel.
Our Gulf of Mexico and Arctic Ocean Oil/Gas infrastructure would certainly be targets for opposition forces desiring to cause disruptions to the US Economy directly and the World Economy indirectly.