And this is in peace time. In my broad and deep but unclassified knowledge there is not another gps cloud in orbit.
But, since Korea has launched satellites and China must have some orbital navigation assets. It is possible our GPS constellation would not be used. Inertial nav could be backed up by just one or two satellites.
We will turn it ofF, completely before we let anyone use it against us. And didn't de-rez the entire system during Desert Storm? Who knows what they have now? It's much better to let us think they aren't spy assets also.
And I'm quite sure specific birds within the horizon of a weapon can send false timing returns. They may be able to tight beam those returns to spoof the signals only to one weapon, area, etc. What ever they tell us the military surely has encrypted bands on their birds to not depend on the civilian sats.
However, I was reading just now that there are 31 Sats left from 59 launched over all, in the GPS and they have not launched one in a while.