Comment by jhbadger
This could be really useful in the future. NIST has been talking about retiring its radio-syncing signal, as there are better modern alternatives with satellites, the Internet, etc. But last time they suggested this there was an outcry, not just from the public with old radio-synced clocks and watches, but also industry with legacy equipment using it. This provides a solution.
Satellite-based time signals also seem easier to spoof, given the inherent power constraints of the transmitters.
That said, newer ones can use authentication, which (together with a reasonably accurate local oscillator) can prevent at least trivial spoofing.