It's like Rahm Emmanuel said: "never let a tragedy go to waste."
There are some sick, power-hungry people on both sides of the aisle. Are they evil enough to carry out an attack like 9/11? No... but don't think for a second that it wasn't seen as an opportunity to grab more power and trample on our liberties nonetheless.
We're seeing much of the same things with the gun control argument nowadays in the wake of tragedies like Aurora and Sandy Hook. Gun-grabbers start up the same old intellectually-dishonest cases to grab law-abiding citizens' guns before the victims' bodies even cool down. It's disgusting.