"What would you do if GPS went out, permanently?"
The whole room collectively didn't want to think about it. There doesn't appear to be a plan. We've collectively put all our eggs in one basket.
* https://rntfnd.org/wp-content/uploads/National-Timing-Resili...
A roadmap was published in 2021:
* https://www.transportation.gov/pnt/national-timing-resilienc...
And also from 2021, NATIONAL R&D PLAN FOR POSITIONING, NAVIGATION, AND TIMING RESILIENCE:
* https://bidenwhitehouse.archives.gov/wp-content/uploads/2021...
The simplest solution is to simply to resurrect the Loran infrastructure that the US (and others) run until the 2000s. The Koreans have been running eLoran for a while, and the UK and France are teaming up as well:
* https://insidegnss.com/uk-and-france-renew-ties-resilient-pn...
* https://rntfnd.org/2025/11/12/s-korea-leads-meeting-with-u-k...
Chinas has had a completely built out network (including fibre networks for high-precision timing) for over a year:
* https://rntfnd.org/2024/10/03/china-completes-national-elora...
This is not rocket surgery: a working system that can giver you continent-wide coverage can be up and running a few years, with little technical risk (there's already kit available).
Throwing some money at the problem and instructing the DOT/DHS/whomever to issue an RFI/RFP would go a long way to moving the ball forward.
A +20dB gain means that the jammer is going to need roughly 100x its current power output to maintain the same effectiveness. An adversary ramping their transmitter by this much would turn into a blazing hot target in terms of electronic warfare. There are entire classes of weapons designed to lock directly onto signals like this. The AGM-88 is an example.
https://www.npr.org/2024/09/27/nx-s1-5127737/losing-gps-woul...
https://www.nbcnewyork.com/news/business/money-report/losing...
Fortunately someone recently posted a real technological wonder - the F-14 cpu, old timers were messing with multithreaded compute while I was muddling along learning pong line by line from a hobbyist magazine.