Actually, From all reports they only succeeded at 50% of their goal. Apparently the plane which hit the Pentagon was actually slated for the White House; The plane which went down over Pennsylvania, was not intended to crash in an unpopulated area it would seem safe to guess.

'--' at will, but I wanted to make sure that no one was really operating under the idea that the people who planned this were so good at planning to be seen as people who can execute something "essentially flawlessly". From all reports, all it took to quash 25% of their year plus of planning was a couple of courageous Americans;

BTW, I did not '--' the original poster.