GPS Sole Source Civil Aviation Navigation?

SirRichardCraniumEsq. wrote:
Has any thought been given to the disparity in altitude
between spy camera satellites and the GPS constellation?

SNIP


Working with the speed of light(LASER)it probably does not
matter that much.

If the Chinese can hit a spy satellite I am sure they can
figure out a way to zap a GPS bird. If not right now soon in
the future.


Aiming for a target 200 miles away is much different than aiming for
something 10,000 miles away. Also, it is not the speed of light, but
the beam diffraction that becomes a problem. You have to concentrate a
lot of energy in a small area to cause any damage, and that becomes
progressively more difficult for distant objects. I am not saying it is
impossible, but the comparison is like firing a shotgun vs firing a
missile.