Post-9/11, if anyone tries to hijack an airplane they're going to have every able-bodied male between the ages of 18 and 40 come at them with the expectation that they're fighting for their life. I know I personally would take my chances that they don't have a bomb: if I do nothing, I would assume I am definitely going to die. If I do something, the passengers collectively could overpower them and hope were bluffing about the bomb. If they weren't, it's the same outcome as doing nothing.