While the fascinating preprogrammed technology means no cost to human life, the methods by which a military can communicate with the craft through water are very different from those used above the waves. “Anytime you’re going to put something under the ocean there, you can’t communicate with it very well. It is fundamentally harder and more complicated to put things under the water,” Fotheringham says. “We don’t have the luxury of being able to communicate with vehicles when they’re a couple of thousand metres down – communication gets very difficult. “Because a lot of the proliferation of drones in the...