As a presidential candidate, Donald Trump praised autocrats and exhibited strongman tendencies. But as president of the United States, Trump is proving to be one of the weakest, most disinterested executives in memory. He seems happy — even eager — to be both operationally and ideologically marginalized inside his own administration. This is, I think, the best way to understand the ouster of chief strategist Steve Bannon. White House staff, congressional Republicans, military leaders, and executive branch officials are increasingly confident simply ignoring President Trump. After Trump tweeted that he wanted the military to ban transgender service members from serving,...