Once this arms race has begun, things can’t just go back to normal. It escalates: A company sees how easy it is to plant stories online and hires a firm to attack its competitor. Blindsided by the bad publicity, the rival hires a firm to protect itself—and then to strike back. Thus begins an endless loop of online manipulation that can cost hundreds of thousands of dollars. And that’s the easiest of the PR battles a company may have to face.