Lyndon B. Johnson assumed the presidency in the wake of the assassination of John F. Kennedy in November of 1963. He gave his Speech to Congress on Assuming the Presidency five days after the assassination, pledging to advance the domestic programs and initiatives of his predecessor and, in foreign affairs, to balance U.S. military strength with restraint. He met with success on the first front but is considered to have failed on the second. In trying to deal with the worsening military situation in Southeast Asia, he made the fateful decision, in 1964, to expand American involvement in South Vietnam—despite the uncertain military intelligence concerning North Vietnamese aggression in the Gulf of Tonkin. In his Remarks on the Gulf of Tonkin Incident, delivered August 4, 1964, he lays out the rationale for a military response in the region. The wider war that Johnson had promised to avoid soon became a reality, but by 1968, when he left office, the United States had still been unable to prevail in Vietnam.