Ken writes:
> Mark alludes to a potential downside:
> > Exactly what the HELL are they thinking!?  Now my ex will
> > be able to locate and target my house.

And won't Mark's neighbors be happy that they don't have to worry about
"collateral damage" :-)

> Another key driver for doing this was the projection that if the
> US didn't give the world better GPS accuracy, eventually
> somebody else would....

Basically everyone already has.  The Coast Guard has spent perhaps a billion
dollars developing Differential GPS for Marine use, which counteracts SA by
measuring the "error" and broadcasting correction information.  The FAA has
been working on a WAAS (Wide Area Augmentation System), which does the same
thing for aviation.  Numerous companies and governments around the world
have gotten into the business of providing different forms of Differential
GPS.  There is at least one (maybe two?) DGPS providers which you can
subscribe to in the US and get GDPS corrections via an AM broadcast
subcarrier.  There are several similar options in Europe, I believe.  There
has even been discussion (and maybe some progress) on doing an
Internet-based free, wide area, DGPS system.

Probably the biggest reason that SA is getting turned off is that it's a lot
cheaper than the alternatives (i.e. just give people the good data rather
than making everyone spend a lot of money to end up with the same thing).

G.