There is already a 2 tier system. Clinton turned off "Selective Availability" but kept the P(Y) code for military only use. The P(Y) code now has been supplemen

There is already a 2 tier system. Clinton turned off "Selective Availability" but kept the P(Y) code for military only use. The P(Y) code now has been supplemented by an M code for military on the newer generation of GPS.