What I know concerns me. What I don't know concerns me even more. What people aren't telling me worries me the most.

Most governments lie to each other. That's the way business gets done.

Even when I was at CIA, I'd go to visit foreign leaders and I'd say, 'You know, I'm not a diplomat. I'm just an old CIA guy'... I said, 'If I wanted to be diplomatic, I'd have been a diplomat.'

I will always be an advocate in terms of wars of necessity. I am just much more cautious on wars of choice.

Often, loyalty means telling people things they don't want to hear. It's not being sycophantic, it's not telling them how wonderful they are every day. It's being willing to tell them the days they're not wonderful.

I consider myself a Republican.

Future U.S. political leaders – those for whom the Cold War was not the formative experience that it was for me – may not consider the return on America’s investment in NATO worth the cost.