SA (Selelective Availability) was disabled in 2000 by an act of Congress and according to gps.gov

>The United States has no intent to ever use Selective Availability again.

I wouldn't be surprised if SA was turned off during that war.

I was out of the USAF by this time, so I have no direct knowledge. But I imagine they did a risk assessment over the possibility of the Iraqi forces gaining access to GPS, either because they bought commercial receivers, developed their own, or got loaned some from more-capable country who would have liked to have seen the US + coalition fail.

They didn't "turn it off" as much as set it very very low, maybe even to 0. But even then, military grade receivers still enjoyed 1-2 magnitudes of improved accuracy.

Clinton turned it off after surveyors figured out differential GPS, which essentially made it obsolete.