A look behind the scenes at how H.R McMaster adapted from the military into his role of National Security Adviser, and the reality of dealing with a boss who takes in little of what you say. His solution was straightforward – “If Mattis was a babysitter, then McMaster was a waiter, presenting the Commander-in-Chief with a menu, and letting him order.” What this didn’t necessarily allow for was any questioning of what was going on the menu.