I have served with Mattis and talked to him personally.
My gut feeling then and now, is that he was a much better Marine, than in the political scene. Many flag officers get like this when they hang around DC after they retire. They never go back to the real world and find out that not everyone thinks like inside the DC beltway.
I still know a bunch of senior Marines from my career. I don’t know a single one not backing Trump. Trump is very well respected in the higher ranks of the Marine Corps. Bank on it.
I served under Mattis too. I thought he was a total poser POS then and when Trumped picked him, I had a feeling it wouldn't end well. Mattis fancies himself a warrior's warrior and innovative strategist. Fact of the matter is... he's neither. The best he could muster are old, recycled ideas he read about in books written by actual innovative warriors.
Frankly, I have no respect for today's general class of officer and Mattis is my front of mind example why. Couldn't win a war to save their fuggin lives... still pushing failed counter insurgency doctrine ~20 fuggin year into these wars and have yet to bring home a win. That and they'll sell out true warriors in the blink of an eye to advance their careers.
I can't decide what's worse... how much sucking off they have to do or how many people they have to screw to make it into the club.