Olga Khazan:

Millennials don’t always buy cars. But when they do, they apparently buy SUVs.
 
 “The floor at this year’s Los Angeles Auto Show will look a lot like America’s roads: full of SUVs,” the AP wrote this week. Car sales overall are actually slightly down this year, but SUV sales are up 6 percent.
 
 The AP speculated that the boom in Wranglers and Explorers is the result of “a combination of low gas prices, growing millennial families, and a host of new models.”
 
 But according to the authors of The Spirit Level, a book about the human costs of social inequality by epidemiologists Kate Pickett and Richard Wilkinson, skyrocketing SUV sales could also be tied to declining levels of social trust in U.S. society.
 
 Fewer Americans now agree with the statement “most people can be trusted” than at any point in the past 40 years, and plummeting social trust tends to motivate individuals to make decisions that will protect their own family, class, or tribe.