Bloomberg campaign adviser Tim O'Brien, the man who wrote the book on President Trump, shares his unique insights into Trump's psyche and how that knowledge is shaping the Bloomberg campaign's media strategy. "Donald Trump is a deeply insecure man, despite the bluster, despite the bravado... and it's very easy to keep him off balance," he says. "First and foremost you have to be fiery with Donald Trump... but if you're going to go to battle with Donald Trump you still have to go to battle with him honorably."

Source: CNN