> You're oversimplifying. US residential power is currently supplied by a pair of 120 V wires, but most of the stuff in your house only uses one leg of that pai

> You're oversimplifying. US residential power is currently supplied by a pair of 120 V wires, but most of the stuff in your house only uses one leg of that pair. That's alright because it's AC, and the ground wire doesn't actually need to carry any significant current. Power just returns time-lagged through the same wire when the voltage changes. This isn't how it works.