The United States should not have to intervene in every single problem around the world. The voters of this country are reacting in a very big, broad way to Mr. Trump. They are frustrated by lousy decisions made by both George W. Bush and Barack Obama. Look at the mess we have.

Why is it that the U.S. has to take refugees? Why doesn't Saudi Arabia take more.

Donald Trump is a great listener, and he's a good challenger. He doesn't come across as a person who thinks he knows it all. In fact, he once told me he has had lot of things to learn.

NATO as a political alliance does need to be relooked at in terms of everything - resourcing, capabilities.

One thing I agree with Donald Trump on is, there's something going on in the Muslim world.

What I know is it is a disservice to those who continue to serve to think that there's going to be a civil-military breakdown because those who serve, they know who they serve. They know what their loyalties are, that's why you take an oath to the Constitution and your loyalty lies in the chain of command and your buddies. That's always been there. We are a professional military.

Obama's decision to leave, to not sustain the victory that resulted after eight years of fighting, from 2003 to 2011 in Iraq, was another incredibly stupid decision. It was totally based on politics, not based on any notion of national security. It's a nightmare for our national security. And then you have the Libya intervention.