Flying Binghi
It's only recently that the Europeans and USA agreed to have some commonality and interoperability on some of the civilian signals, so we'll need to wait until new GPS receiver-frontends are built or old ones upgraded.
It'll still mean that they can both switchoff or degrade their signals when required and anyway, Galileo & Compass are still quite a few years away from being operational so in the interim we are reliant on GPS and GLONASS.