Now, as in his own time, Calhoun's voice resonates to fundamental concerns of American democratic polity: the nature of man, the obligations of government, and -- most keenly -- how best to safeguard the interest of a minority against the will of democratic majorities. His doctrine of concurrent majority and a minority veto -- although employed to defend the South's commitment to slavery in pre-bellum 19th Century America -- strikes an enduring question of how a diverse, and sometimes divided, society can maintain its integrity while honouring the interests of all its citizens.