Spikes of corn stalks are scattered along miles of fog-shrouded fields in Hancock’s Bridge on a spring morning — an eerie suggestion of the bayonets used in the Revolutionary and Civil War battles that were fought there. On the horizon is the billowing cooling tower of the Salem Nuclear Power Plant, which is taller than the length of a football field. It is a stark reminder that this historic rural hamlet relies on an industry that is playing a major role in the nation’s debate over energy policy. The contrast is not lost on Ellen Pompper. Her family moved to...