They live in the suburbs of Tennessee and Indiana. They fought in Vietnam and Desert Storm. They speak about an older, better America, an America that once was, and is no more. And for the past decade, they have come to the U.S. / Mexico border to hunt for illegal immigrants. Who are the Minutemen? Patriots? Racists? Vigilantes?

Harel Shapira lived with the Minutemen and patrolled the border with them, seeking neither to condemn nor praise them, but to understand who they are and what they do. Challenging simplistic depictions of these men as right-wing fanatics with loose...