Did they do all they could have done?

Here in Spain there has been a lot of fuss about the obvious American vulnerability to terrorism but most of that was centred in intelligence defaults. I think thatif you analize the situation you found operational problems too. The first plane hit the tower at 08.45, the second at o9.05 and the last hit the Pentagon at 09.45. It´s easy to asume that the first could be misunderstood as an accident but since the second impacted in live Tv, I saw it! nobody dhould have the sligthest doubt. Well, we are talking about 40 minutes, in 5 Washington should have been protected by half a dozen F-15, and if we are talking about autorization for shooting something down, comunications travel at the speed of ligth. I´m i wrong?