Surveillance and Reconnaissance Space-based signals interception is critically and uniquely complemented by submarine intercepts. Submarines also provide sole source tip-off information, which enables the intelligence community to optimally allocate other intelligence collection assets.
Submarines see things our satellites miss.
Because submarines are unpredictable and operate undetected continuously for weeks at a time, they prohibit the enemy from timing operations to deny or deceive collection efforts. Because submarines are close to the action, they can capture signals that are too elusive or enveloped in background noise for our satellites to detect. Submarines provide undersea situational awareness. Submarines can acoustically monitor undersea events and phenomena not detectable by any other sensor. Intelligence gleaned from such submarine operations range from the highly technical details of military platforms to knowledge of a potential adversary s operational doctrine and prowess.