Hunting submarines is dull, dangerous work. It's an elaborate game of sonar-fueled cat-and-mouse in vast stretches of open water, where the stakes are "finding foreign nations' seaborne nuclear weapons," or finding the foreign subs looking for our own seaborne nukes. DARPA, the Pentagon's future-war focused agency, wants to make it easier to find submarines, and they're enlisting robots to do it. Giant, full-sized, ship robots: