Every so often, the media likes to warn us that we're all dying from air pollution.

Headlines like, "Air Pollution 'Kills 7 Million People a Year'" are common and repeated like a morose version of the childhood game "Telephone." Predictably, that leads to calls for tighter environmental regulations, and anyone who disagrees is labeled an Earth-hating, cancer-loving industry shill.

Now a team of researchers from the University of Chicago has created a map that depicts the average number of years of life per person that could be saved if countries adopted the...