>Everyone sharing four increasingly redundant systems starts to look like a waste of money

straight out of the "having two kidneys is a waste of energy" school of thought

You could buy yourself a dialysis machine "just in case" but you will have to give up something else to afford it. There is a trade off.

What level of redundancy is needed? Having three global systems seems reasonable, if it's an important service.

the problem with just one is that US will insist having a deadswitch on it, just like it did with Galileo.

so you must have your own if you don't want US to have a Damocles sword over you

Newer GPS satellites apparently don't support selective availability, so they would have no way of preventing access to only civilian devices. Of course, any of these systems can be jammed or shot down but that would affect anyone using it.

> In September 2007, the U.S. government announced its decision to procure the future generation of GPS satellites, known as GPS III, without the SA feature. Doing this will make the policy decision of 2000 permanent and eliminate a source of uncertainty in GPS performance that had been of concern to civil GPS users worldwide.

https://www.gps.gov/systems/gps/modernization/sa/

Why would a reformist country like China and Russia trust such a thing. We were also told that mass surveillance was a conspiracy/nutjob story, but the Snowden leaks has shown us a different world.

They wouldn't, and I can see why. I was just adding some information. As far as anyone in the public has been told, both GPS and Galileo will remain open for anyone to use, but depending on that requires trusting whoever runs it.

If I wanted my neighbours to trust my GPS system more, I'd tell them I don't have selective availability.

Sure. If you wanted GPS to be more widely used and depended on with no ulterior motives, you would also tell them you don't have selective availability. All of these systems require trusting the operators at the end of the day, and I'm not making the claim that one should depend on any single system.

It stops looking that redundant when one system goes down because both of its ground based refence clocks go down at the same time. This recently happened to Galileo. Nobody noticed because NavStar and GNSS covered for it.

NavStar GPS can keep on running for quite a while even if the entire ground segment fails. The current generation of satellites even have an Autonav mode that lets them synchronize their clocks and compute corrections to their orbital parameters using cross-links between satellites without any ground assistance. Supposedly it can provide almost full accuracy for six months after a complete failure of the ground segment. Galileo just isn't very robust by comparison.

If everyone is thinking the same thing, then someone isn't thinking. (This time, I wasn't thinking, but I agree with the sentiment.)