> So someone gets a notification he has landed in Miami - are they going to race to the airport, hop the fence, run to his plane and confront him?
Even if congress shutdown ADS-B receiving or encrypting it somehow, people would just get out the long range camera lenses and take pictures of the tail numbers as the planes land and report it on a web site.
ADS-B is used all over the world, the trend is actually in the opposite direction: more and more airspace requires the use of ADS-B. Encrypting it would defeat the purpose of allowing airplanes to see each other as well (ADS-B to some extent replaces radar).
Congress could presumably pass some law but it would have to be ICAO or some other global organization that would formalize the change. Updating the systems on all aircraft would take many years. The current roll-out has been in progress for more than a decade.
Even if congress shutdown ADS-B receiving or encrypting it somehow, people would just get out the long range camera lenses and take pictures of the tail numbers as the planes land and report it on a web site.