Finally, McMaster's decision to stay on active duty even as he serves in the Trump White House could make it harder for him to disagree forcefully with the president or other senior administration officials. "It is a lot easier to say 'Screw this job' or 'I am not doing that' as a civilian," said a friend of McMaster, who spoke on the condition of anonymity to be frank. "It is the ethos of the military to do what you are told whether or not you like the mission or the chain of command."