“This is something he can do by himself?”
You think 0bama would not authorize a dirty bomb against an American city, say, in the heartland, in a red state?
It doesn’t have to be a push of a button. It could be a text message or a private phone call to John Doe.
I would not doubt your second sentence is already in the works. But that still isn’t the same as what most think of when hearing “Nuke a city”.