Originally Posted by ja_user
I think what your forgetting, is that if someone doesn't have the password and doesn't divert to IAD, they can easily be shot down. Whether this would actually be done to a 737 full of poeple becuase of a missing password is another story, but the pilots diverting is more of an idication of who is flying.
I'm not forgetting it - if that's the case then why don't they have passwords for all airports? How is this any different for a flight that is scheduled to go to IAD, but instead of landing there makes a sudden turn towards DC? I don't know about you but I don't think fighter jets can scramble that quickly.