I think when it comes to the issues, I'd advise him to stick to the script. But, I mean, Donald Trump is going to have some very tough conversations and he's going to be talking about some very tough and complicated issues in all of the places that he visits.I think anytime a president does things that are humanizing, I think it's - it's good.

In my opinion, any future defense secretary who advises the president to again send a big American land army into Asia or into the Middle East or Africa should 'have his head examined,' as General MacArthur so delicately put it.

I don't think any president that I worked with has ever said 'pretty please.

Congress is best viewed from a distance—the farther the better—because up close, it is truly ugly. I saw most of Congress as uncivil, incompetent at fulfilling their basic constitutional responsibilities (such as timely appropriations), micromanagerial, parochial, hypocritical, egotistical, thin-skinned and prone to put self (and re-election) before country.

One of my favorite little sayings is, 'To avoid criticism, say nothing, do nothing, be nothing.

If possible, to be in a position to announce who is going to step in as the interim immediately. And if possible, to announce who you're going to nominate to replace that person. For that to be somebody of impeccable integrity and reputation disarms a lot of the worst criticism that it's some kind of a power play. It's a professional approach to replacing a senior official, which is always going to get a lot of attention.

There is no international problem that can be addressed or solved without the engagement and leadership of the United States and everybody in the world knows that, its just fact of life. So sometimes I think we could conduct ourselves with a little more humility.