Immigration is the most difficult issue I've ever dealt with, and I've dealt with some tough issues: drones, gays in the military, WikiLeaks, Guantanamo. But immigration is hardest because there are so few people willing to talk and build consensus. Everybody's firmly made up their mind. It's a polarized issue.

In my view, targeted lethal force is at its least controversial when it is on its strongest, most traditional legal foundation. The essential mission of the U.S. military is to capture or kill an enemy. Armies have been doing this for thousands of years. As part of a congressionally authorized armed conflict, the foundation is even stronger.

ISIL, AQ, now have the ability to literally reach into our homeland through social media, through the Internet, to recruit and inspire. It makes for a more complicated homeland security environment. And so it requires a whole of government approach, not just military and law enforcement, homeland security, aviation security, and the like.

How could somebody be comfortable with authorizing legally the use of lethal force? My view is if you become comfortable with it, then you should get out of the job.

I simply told people what I thought about the state of the war in Vietnam, and it was that we better get out of this.

War criminals in the U.S. and Israel are not punished: no international court has the courage to put them on trial.

I admire President Chavez for his strength to resist the United States. Instead, Bush is waging a war of terrorism against the world.

The U.S. does not want to live under the shadow of a North Korea that possesses long-range missiles capable of delivering nuclear payloads to American cities. At the same time, the U.S. has no appetite for a war that would prove costly by every measure.