Much of the industrialized world is dotted with no-go zones. Toxic sites. Chernobyl. Old tannery sites and battery factories in London are fenced off. They sit empty amidst Europe's most densely crowded city. In my old home state of Missouri, Time's Beach is abandoned by humans--too many PCBs in the soil. And in Oklahoma there's a town so toxic nearly everybody has moved out. Lead mining for decades with little or no concern for the consequences left poluted water and soil. You might wonder if our current pollution of the atmosphere is on a similar track.