Yes but they also have mack daddy radio comms and sat cells.
I’ll surmise that the feds (states cannot afford it) have their own subnet.
Feds do have their own GPS sats. The loss will come from cutting the internet and power to Garmin, Delorme, and Google etc... servers.
Unless you have a generator store bought batteries will be depleted in less than a week then how do you charge?
If goat herders in Afghanistan can field a credible force to preserve their way of life, can we do no less?
You need to go to Battery1234.com to see how you can keep your devices charged when the power is cut.
One marine battery will charge a smartphone thousands of times.