What is the price of staying connected, of that phone in your hand or that watch on your wrist? Recent TV shows would have you believe that the most dangerous job in America is a crab fisherman, or maybe even an ice road trucker. But what U.S. Department of Labor unequivocally recognizes as the most dangerous job in America belongs to the tower dog, the men and women who work on cell towers across the country, building the networks that keep us all connected.

In Tower Dog: Life Inside the Deadliest Job in America, Douglas Scott Delaney, a tower dog for more than fifteen years,...