In order to be successful against each of these threats, we have to have a presence overseas, work closely not only with our counterparts in the law enforcement community, but also with the intelligence community.

If you look at the 19 hijackers who came to the United States in Sept. 11 to commit those acts, if you'd looked at them before they got onto a plane, you could probably say the same thing. There were various levels of expertise, various levels of competence.

I would say in just about every investigation we have, there will be differences of opinion, where you have partial facts, as to what those facts mean.

I was in my office when - on 9/11. I think I had a number of meetings scheduled. I was just getting to know the bureau. And somebody walked in and said the first plane had - or a plane had struck the World Trade Center, one of the towers.

I think around the world, our agents are the best collectors of information you'll find.

I know when I was here prosecuting homicides in the District of Columbia, one of the most effective units here was the cold case squad, which had on it FBI agents, as well as Metropolitan Police Department homicide detectives working together.

In planning an attack, persons have various roles.

I asked a Burmese why women, after centuries of following their men, now walk ahead. He said there were many unexploded land mines since the war.

But we had - I think if you look at law enforcement 10 years ago, if you look at the challenges, the FBI was focused excessively on what was happening in the United States.

But since September 11, we have made every effort to try to work closely with state and local law enforcement.

As I said before, there are often disagreements as to what a particular set of facts mean. That is not at all unusual, and one shouldn't read into it more than is there.

And from the moment that we realized it was a terrorist attack, there isn't an agent or a support person in the FBI that wasn't committed to bringing to justice those who were responsible for this.

All I'm going to tell you is investigations, whether it be this and others, where you have partial facts, analysts, agents are always trying to interpret what those facts mean, extrapolate from them what they mean.

In the context of September 11, there were so many that lost their lives that - how do you single out one person? There were so many acts of heroism that day from so many people, whether it be firemen and police officers in New York and our agents also.

It's because we need to determine who in this country is poised, positioned to commit terrorist acts.