You know we have to build roads for the cars to drive on right? Wonder what the C02 emissions for a mile of new highway is. You're also not accounting for the construction, transportation, maintenance, and other CO2-producing activities for cars - none of which are necessary for walking. Nevermind the other benefits like attacking obesity and deaths due to car crashes.
> 1. Get people into electric cars, which even on the current grid cuts your CO2 emissions by over half due to better efficiency, then
> 2. Convert the electric grid to 100% clean energy.
These both need to happen, yes. Cars existing is fine, just need to reduce usage for daily activities by 90% or so and also convert most of the grid to clean energy.