How did the world react after John F Kennedy 's assassination .
He served as organizer and director of Kennedy 's presidential campaign schedule in 1960 , as Kennedy 's special assistant and appointments secretary 1961–1963 , as Lyndon Johnson 's Presidential Aide 1963–1965 , and as campaign manager for Robert Kennedy in the 1968 presidential election campaign and , after Kennedy 's assassination , for Hubert Humphrey .