American civic engagement soared in the mid-twentieth century, succeeding an era in which national government had become more involved in citizens' lives than ever before. I examine the effects of the G.I. Bill's educational provisions for veterans' subsequent memberships in civic organizations and political activity. I consider theoretical arguments about how public social programs might affect civic involvement and advance a policy feedback approach that assesses both resource and interpretive effects of policy design. Newly collected survey and interview data permit the examination of several hypotheses. The analysis reveals that the G.I. Bill produced increased levels of participation—by more fully incorporating citizens, especially those from less privileged backgrounds, through enhancement of their civic capacity and predisposition for involvement. The theoretical framework offered here can be used to evaluate how other public programs affect citizens' participation in public life.