Screaming Penguin - Source Does Matter

GPS is incredibly important to all sorts of devices, tasks and even industries. Its also potentially a problem if enemies decide to use it against you to locate targets or coordinate their own movements.

As such President Bush has decided to sort of reinstate a system called "selective availability". In this system the US plans to have the ability to disable sections or portions of our own GPS system and that of others.

This would be accomplished by in effect "jamming" the satellite signals (yes that does conjur up the notion of Rick Moranis in Spaceballs, "JAMMED, grape!").

This new on off availability would only be used in the most dire of circumstances and sounds prudent to have as a capability (IMHO). For more see the linked AP article via Yahoo News!   Bush Prepares for Possible GPS Shutdown