Historian McCullough says Kennedy's words changed history and still apply today

Author and historian David McCullough says John F. Kennedy's words changed lives and history. And he says much of what Kennedy said still applies today.

McCullough read excerpts of some of Kennedy's most well-known speeches Friday during a Dallas ceremony on the day marking 50 years since Kennedy was cut down by an assassin's bullet.

He says Kennedy spoke of things that mattered, including education, service to one's country and the cause of peace on Earth. And he says Kennedy spoke to the point, with confidence and without "stale platitudes."