Obama's endorsement of gay marriage is hardly as consequential as Johnson's legislative success on civil rights.

As for Vietnam, what matters is that Kennedy successfully resisted pressure to send anything more than military advisers, a stance that was a likely prelude to complete withdrawal from the conflict. There is solid evidence of his eagerness to end America's military role in that country's civil war.

Whatever the long-term legal prospects for same-sex marriage, President Obama's willingness to put the matter front and center in an election year can at least make him a candidate for inclusion in Kennedy's Profiles in Courage.

Robert Dallek Quotes