Wifi's range is too short to make a large mesh network genuinely feasible. Even in densely populated cities you're going to have gaps where you need to cross a

Wifi's range is too short to make a large mesh network genuinely feasible. Even in densely populated cities you're going to have gaps where you need to cross a street. That'd require directional antennae and a huge amount of deliberate effort and maintenance to hook up a large area. Must have longer omnidirectional range and some degree of wall penetration. I'm not sure if that's possible within reasonable FCC limits of frequency and power.