Here is how I see what he is doing. He is basically a frat boy with little Washington experience and great ideas, to him. He is an ideologue that thinks his ideology is the right one. Now who doesn't think that way? Where he goes wrong is he doesn't wish to work, or more importantly doesn't know how, to work with the opposition. Thus the lack of Washington experience causing trouble.
I feel he really believes that opposition to him is not because of the merit of the idea but for other reasons, such as being black or a democrat. So in order to get what HE thinks is right done, he has to resort to what he is doing.
Does he do what he does just to show how powerful he thinks he is, no. I believe he does it for more insidious reasons, he thinks he knows everything and he is always right. But big egos in Washington is certainly not new.