Office romances are fine. Even in the military, relationships between coworkers are accepted. It’s part of life. What’s not accepted is hitting on or dating your subordinates. One, it’s inappropriate since the subordinate may feel forced to comply with the advances for the sake of his or her career. And two, even when it works out and isn’t harassment, team dynamics are about to go into the toilet. Who gets the next promotion? Who gets the next good deal assignment? When the boss is dating one of the team members, any decision will be suspect. The whole thing is entirely unprofessional. An office romance between consenting coworkers is different from harassing/dating people you have power over.