"...when there are a large number of very powerful Military transmitters already operating in the VLF band." To my knowledge, no military TXes are being used f

"...when there are a large number of very powerful Military transmitters already operating in the VLF band." To my knowledge, no military TXes are being used for that purpose. I did outline how the system might work, that is similar to the structure of cellular phones. Moreover, there's no indication there's enough military TXes around to allow for accurate triangulation, nor is there any indication or guarantee that the military will have them running 24/7, which is a prerequisite. SID is all very well and to be welcomed but someone or entity has to run the service after the science (via, say, SID) has been established. Any entity running such a scheme has to work across national boundaries—has to be international. Chances of that happening anytime soon other than through AR are just fanciful. AR has a long history in civil defense and emergencies and has international representation through the IARU https://www.iaru.org/ https://www.iaru.org/ which has been around just on a century and has representation at the ITU in Geneva. It's in a pivotal position to argue the case internationally. If you've a better, more practical solution then let's hear about it.