And so we try to address those concerns in every way possible, recognizing, again, in the final analysis, everybody on that flight wants to be assured with the highest level of confidence that everybody else on that flight has been properly screened, and including me and you and everybody.

The bottom line is how do we best provide for the security of the traveling public in light of a determined enemy who is adept at constructing well-designed, well-concealed devices which would not show up in a walk-through metal detector? We're trying to employ the best technology to identify any possible threat.

The bottom line is, if somebody doesn't go through proper security screening, they're not going to go on the flight.

We put people of concern on the watch list or the no-fly list, so we have a number of layers of security beyond the airport checkpoint. We gather as much information about a passenger as the law allows without profiling.

I particularly recognize that reasonable people can disagree as to what that proper balance or blend is between privacy and security and safety.

We save limited resources in terms of who we are physically screening. The approach will allow us to pay more attention to those potential terrorists.

The reason we are doing these types of pat downs and using the advanced imagery technology is trying to take the latest intelligence and how we know al Qaeda and affiliates want to hurt us, they want to bring down whether it is passenger air craft or cargo aircraft.