Besides LORAN-C, there used to be another low frequency radio navigation system even better suited for global shipping: Omega. It operated on even lower frequencies, in the 10-14 kHz (yes, kHz) range, and had worldwide reach unlike LORAN-C which was only regional. It was shut down in 1997.
Jamming and spoofing are the much bigger threats.
Marriott's reply is laughable. It might work on unsophisticated readers but not anyone who knows anything about WiFi. They said they wanted to "protect" their guests against "rogue" access points. Well, if those "rogue" access points were spoofing Marriott's own SSID, they might have a point. But I certainly don't set my own portable hotspot SSID to that of any hotel. It's set to something quite unique, and it's encrypted. Nobody is going to mistake it for a hotel's network, much less actually associate with it.
CO2's atmospheric lifetime is something like 1,000 years. How come those who fret about the longevity of nuclear waste never seem to talk about this? With fast reactors that burn the actinides (including plutonium) as fuel, the remaining fission products decay to the level of the original uranium ore (while being considerably more compact) in only a few hundred years, much less than the atmospheric lifetime of CO2.
The hype about "carbon capture" is just that -- hype. But it serves one useful purpose: its utter impracticality shows just how minor the nuclear waste "problem" is by comparison.