Benghazi. He dispatched fighter planes to Benghazi without clearance from the WH.
He was relieved immediately - at sea, and then mysteriously, complaints were filed that he had used "swear words" at a crew man and that he said another officer was promoted because of affirmative action rather then merit.
Like Michael Flynn, he had no chance. The accusations may as well have come from Blasy Ford herself.
Trump is clearly not cleaning his trail up like Obama did.
All of that aside, your opinion is simply based on who is president, nothing more. This will also be the reason that you will oppose his efforts to recover from COVID - though you will not see it that way. You will not trust Trump no matter what. You will see his decisions as wrong even though your own candidate might have made the same decsiion in which case you would have seen it as correct.
This is evidenced in your post by your inferred disapproval of the handling of a military event (your posting of the troops giving the dismissed admiral applause), that had nothing to do with Trump by lifetime naval officers that would have done the same thing under Obama that you clearly would have approved of had it been 5 years ago.