Which twentieth-century president am i? i took office following the assassination of the previous president in 1963. i spent the years of my term dealing with the vietnam war. initially i believed military aid and advisors were all that were necessary for the u. s. to assist in stopping the spread of communism. however by 1964, it became clear that the south vietnamese needed combat , and 20,000 u. s. troops were sent to . the u. s. needed to show the world that it would not tolerate communism. i also to pass vital civil rights legislation. calvin coolidge dwight eisenhower franklin d. roosevelt herbert hoover john f. kennedy lyndon b. johnson