this is a very air event. it is unlikely to be repeated, but president bush put his finger on it. we have to find who did this and any country, any nation in the world that is in any way involved or responsible that turns out to be terrorism will require a response from the united states and the united states has to be willing to pay that price. >> we are completely stunned when about 25 minutes after the first plane crashed into one of the twin towers another very large plane did the same thing. we have been talking with our correspondents all morning about if another incident could happen on the heels of these two, what kind of measures are in place to prepare for something else that could happen? >> one of the steps is being taken. i was getting ready to fly to la guardia when this occurred. they have shut down the traffic.