In a discussion forum I encountered an interesting but scary theory about Trump: he likes attention but he doesn't like to manage the details of governing. The last time that happened in Washington DC we had Cheney running foreign policy and talking George into Iraq. George W's own father pretty much confirmed this in his autobiography.
Thus, Trump and his cocky shoot-from-the-hip style may not be the biggest problem with a Trump presidency, but rather who he lets run the show while he's out on the road bragging to world leaders about how great he is.
