Harold Kushner's bestselling book "When Bad Things Happen to Good People" fundamentally transformed American religious thought by introducing Reconstructionist Jewish theology to mainstream audiences. The book's revolutionary premise—that God does not control human suffering but rather helps people cope with it—originated in Mordecai Kaplan's Reconstructionist Judaism yet resonated far beyond Jewish communities. By analyzing the book's theological content and public reception alongside Charles Liebman's 1970 survey data, this research reveals how Reconstructionist ideology had already gained traction among American Jews before Kushner's work, even among those unaffiliated with the movement. Kushner's accessible literary presentation of Kaplan's complex theological concepts attracted both Jewish and gentile readers, marking a decisive shift away from traditional interpretations of suffering as divine punishment. The book's enduring influence ultimately facilitated the broader adoption of Reconstructionist principles throughout American religious communities, effectively transforming Reconstructionism from a specifically Jewish movement into "the ideology of religious Americans"—representing a profound evolution in contemporary American religious thought.