I agree with you and would question only one thing, that is, if "The last thing Trump wants is to appear as though he's a coward", it is too late.

Trump has shown himself to hide behind the deeds of others, to switch allegiances or support whenever it caused him difficulty and to demean and abuse other for nothing other than that he cannot accept criticism. - Al of these behaviours are those of a bully and all bullies are cowards.

As, if not more importantly, he continues to promote mass hysteria arising from genuine feelings of disadvantage by predominantly blue-collar and under-educated Americans, and use this to create distrust, disharmony, conflict, law-breaking, abuse and aggression. This is cowardly, indeed. Not only that but it is deliberately deceitful for these are the very last sectors of society for which he has any concern or with which he any real affinity - they are simply tools to be used to further his own ends.

An ultimate cowardice, denying response for one's own actions and using others to take the blame.