The Secret Service should be in that video, but they are not. It is clear from their inaction that they KNEW FOR A FACT THAT THE PRESIDENT WAS NOT A TARGET OF ONE OF THE HIJACKED PLANES. The intended targets of the planes had to have been known.
The dog did not bark because the criminal was its master.
Quod Erat Demonstradum, the Bush administration was part of the 9-11 plot.