Umm, my point exactly? That a LOT of the crap you see in the air is in fact from construction dust and not just car emissions.
Wow... I mean, just wow. You really don't get it.
I really had no idea this would be so hard for you to understand but please, try to follow me for just a second here. A majority of electric power plants in Arizona are run on coal and gas and with about half of gas ones being in Maricopa county - you know, where Phoenix is. Burning gas produces air pollution. If all cars ran on electricity, MORE electricity would need to be produced and that would mean even more gas would need to be burned. Even if it's a Duracell, you can't just take a pair of AA batteries and use them to light up your whole house, turn on your TV, run your computer and charge up your phone.