After thinking about the stylistic mannerisms of DJT and his pal Mattis, I believe I am approaching the truth.
Trump is a Management by Exception executive. IOW he establishes broad guidance for his principal subordinates, delegates authority to them and sits back to watch the machine run. He then feels free to watch TV news shows, argue with the CIA PDB briefers and intervene on an exceptional basis with his subordinates to give them "course corrections," a-s chewings and/or pats on the head as he probably did with the employees of his sole proprietor company. He also has no inhibitions about making side deals with various other CEO types without informing "his people."
Mattis, the warrior monk, has a highly developed style of management that is not very different from that of his boss. He, too, is a management by exception type. It is now clear that he has returned a lot of power and authority to his subordinates both at the service departments (Army USMC, Navy, USAF) but also in the operational chain of command (CENTCOM, PACOM, etc). He believes in delegating to his subordinates as much power as they think they need.
This sounds great, especially if you have ever worked for the far more common, nitpicking, micro-manager types. BUT, there is a certain cumulative effect when you have two Delegators stacked one on top of the other in the hierarchical world of government. IMO the result can be seen in the case of Syria where military commanders in the field have been given a great deal of freedom of action to pursue what they think we should be doing even as DJT is busy with the TV news, tweeting away happily, and engaged his own pursuit of "side deals."
This results in fitful beginnings and endings, orders from the WH that have no antecedents from the point of view of the forces in the field and frustration of officers who are not accustomed to sudden change and who are generally rigorous rather than creatively spontaneous thinkers. Having watched US military think tanks try to deal with futures they have not seen as yet, I can testify to the existence of a collective absence of "the vision thing."
Well, pilgrims, The DJT/Mattis method is one way of doing business. pl