Bruce Springsteen—“The Boss,” the gravel-voiced poet of the American working class—had said something that split the nation in two.
During a rally in a Midwestern city, standing beneath a banner that read “Voices of the Heartland,” Springsteen had veered off-script. The crowd had expected music, perhaps a few nostalgic reflections about factory towns and fading dreams. Instead, they got a political lightning bolt. “This country welcomes people in good faith,” he had said, gripping…