"Consider the parents of an eight-year-old girl named, say, Molly. Her two best friends, Amy and Imani, each live nearby. Molly's parents know that Amy's parents keep a gun in their house, so they have forbidden Molly to play there. Instead, Molly spends a lot of time at Imani's house, which has a swimming pool in the backyard. Molly's parents feel good about having made such a smart choice to protect their daughter.

"But according to the data, their choice isn't smart at all. In a given year, there is one drowning of a child for every 11,000 residential pools in the United States. (In a country with 6 million pools, this means that roughly 550 children under the age of ten drown each year.) Meanwhile, there is 1 child killed by a gun for every 1 million-plus guns. (In a country with an estimated 200 million guns, this means that roughly 175 children under ten die each year from guns.) The likelihood of death by pool (1 in 11,000) versus death by gun (1 in 1 million-plus) isn't even close: Molly is roughly 100 times more likely to die in a swimming accident at Imani's house than in gunplay at Amy's."