I think a Donald Trump presidency raises a new kind of version of conservatism which more closely resembles a kind of Father Coughlin, America first populism and nativism and isolationism, than the confident, modern, cosmopolitan, thoughtful, engaged conservatism of Ronald Reagan and Paul Ryan.

The dismissal of any of these people would send a useful signal to U.S. allies that the president has the nerve - and self-awareness - to make a change.

I don't think the Republican Party, or I should say the Republican Party as the vehicle for modern American conservative ideas, survives with Donald Trump.

The only person who counts in the administration is the president of the United States.

I have a very, very hard time voting for Mrs. [Hillary] Clinton.

I think a Donald Trump presidency raises a new kind of version of conservatism which more closely resembles a kind of Father Coughlin, America first populism and nativism and isolationism, than the confident, modern, cosmopolitan, thoughtful, engaged conservatism of Ronald Reagan and Paul Ryan.

What is absolutely clear is that if Trump is the nominee, Republicans cannot win. Maybe they can't win with Rubio or Cruz or Kasich. We don't know. But what is absolutely certain is that with Hillary Clinton locking up the Democratic base, she is going to win unless she has a strong contender who is going to be able to pull - not only bring the entire Republican Party on the side, but win moderates. Donald Trump cannot do that.