People seem to trust maps more than other forms of conveying information. It’s one thing to read that a city is racially segregated; seeing it on a map makes it seem more real. Our natural inclination to believe whatever we see on maps makes them excellent tools of persuasion.

This unique power has put maps at the center of many propaganda operations, morality movements, and political debates. Just last week, a map showing which parts of the country would be hurt by a U.S. withdrawal from the North American Free Trade Agreement (NAFTA) helped persuade the president to scrap that plan.

“Almost every child has a recollection of a parent unfolding a road map when you're very young,