Some of the largest defense contractors are increasingly taking positions in the unmanned maritime systems market, buying companies and readying for new Navy programs. The Navy has made clear it plans to spend more on autonomous undersea vehicles. In a 2016 report, the service called AUVs a "key component" of its effort to improve undersea superiority and said it is "committed to growing both the size and composition of the AUV force." Companies have taken steps to prepare. Two of...