WTC Building 7 just happens to get "destroyed by falling debris" when it exhibits a typical pancake demolition collapse. The towers themselves collapse in a very short time, when the fires were already dying down, and then show molten steel, smoke plumes ejected from windows ten stories below, and a rapid descent in ten seconds at near free fall speed, like the floors belows weren't even there. The rubble had twisted, melted steel that smoked for days. The remains of the tower were quickly shipped off before analysis could be done, and flight recorders were confiscated.
Dick Cheney and co just happen to be making money off of Halliburton contracts in Iraq, Afghanistan and New Orleans. The food for oil program just happened to make a lot of individuals rich. Condaleeze Rice has an oil tanker named after her for no particular reason. Larry Silverstein just happened to get a great insurance policy on the towers in case they were destroyed before they were attacked.
It goes on and on, and it has nothing to do with being evil. It's about greed and corruption. It's about the importance of making money for individuals over the importance of making money for nations. To the friends of Bush, it's all about "how much can I make during this term," with the next president being left to pay off debts and try to fix any problems.