​A detail from a 19th-century illustration depicting a slave revolt in Virginia.Credit...MPI/Getty Images

Every mass shooting, like the most recent at Santa Fe High School in Texas that left 10 people dead, reignites a passionate debate over the Second Amendment. For many Americans, if there is an image that comes to mind when they think about that amendment, it is the musket in the hands of minutemen at Lexington and Concord.

A dramatic but little-known
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