Terrorism is really the only existential threat to America as we know it - as a free country that plays a leading role in the world.

There are two great tragedies in life: one is to fail to achieve one's grandest ambitions, and the other one is to succeed.

The fact that there are now many entities that may have some loose affiliation with a former core Al Qaeda - or who have decided to fashion themselves as an affiliate or follower in the Al Qaeda jihadist tradition - as well as groups that are just inspired by the concept that they could also be the perpetrators of mass killing, means that there is a spectrum of threats.

Given that the Al Qaeda core has been significantly destroyed or disabled, and that the leadership seems to be essentially on the run or in hiding, it would lead me to think that probably it is one of the less centralized groups that might be the greatest danger.

And I hope that we can learn the lessons of the past in looking at the current challenge that China poses to a ruling America.

I think we should be organized in something called an Alliance Against Nuclear Terrorism. In the same way that NATO was the great alliance of the Cold War and served a great purpose then, we need now, in the war on terrorism, a new alliance, the mission of which would be to minimize the risk of nuclear terrorist attacks, and the members would agree to sign on to the gold standard.

Terrorism is really the only existential threat to America as we know it - as a free country that plays a leading role in the world.