Mesh networking? The problem you're describing comes being reliant on wires correct?
Mesh networking is an idea that needs development. Part of the developing has to do with legal freedom to use unlimited mesh "broadcasting." With more and more technologically advanced electronics, digitization of more and more intermediate bands is becoming a greater reality on a regular basis. Soon, the legal governing system won't have any reason to keep people from using personal, million watt transmitters, because they will be able to do such without interloping on the legal or off-limit bands.
The problem with mesh will still be interference, if the mesh is broadcast, that is. There may come a time when antennas will be directional "MASER" type and style, that will act unit to unit in a predetermined contact base. Something like this would be very difficult to interrupt without something like a complete EMP blast of some kind. However, EMP protection is available right now, and an EMP blast recovery could be fast, faster than the Arizona cable-cut rebuild.
Another, possibly even greater threat is, electrical grid failure. The advantage of MASER mesh is that power could actually be supplied from one generator, via MASER antennas, to the other members of the mesh. However, personal electrical generation would be preferable.
EDIT: Just a note. Masers are not things that we have little knowledge of. Standard microwave ovens are closed, low-power masers. Aligning two microwave ovens to face each other with open doors, say rooftop to rooftop, could transfer all kinds of high-frequency electronic signals between the two with little chance of interferrence. Properly aligned and focused, power can actually be transferred this way.
BUT... if you do this, be very careful. Standing in front of open-door, microwave ovens can fry you just like standing front of aviation radar... if you are not careful.