Usually, you do a shakeup because you know that you have a problem or you gaps and you're going to fill those gaps.

Even on Ben Carson, he's not exactly steeped in housing policy, but his statements on the issue have also been very conservative.

The Donald Trump call in the president of Taiwan and of itself, as Henry Kissinger said, hasn't created some tremendous trouble in China. But what we don't know is whether this is just posturing or whether this is a policy change.

Lots of people coming in and out the Trump Tower, not necessarily indicative of what Donald Trump policy is going to be. To have Al Gore one day, and the next day the head of ExxonMobil, what does that - what are you supposed to read into that about his stance on climate change? So, I think, again, it's going to be that the actions that he takes are significant.

Hillary Clinton is got to make the case for herself that nobody else can make, and for voters to see somebody who looks more three-dimensional, that's not simply a caricature that had been sort of a part of the American dialogue for the last 25 years.

It was very clear, even from long before Donald Trump got in this race, when he would talk to Republicans, the number-one concern they had about Jeb Bush was whether he was too rusty for this, and whether he was going to be strong enough to stand up to Hillary Clinton.

When Jeb Bush came on the shows and couldn't answer questions about Iraq, and when he looked like he was unsteady, it absolutely solidified the concerns that they had had all along about his skills.