During the spring of 1964, military planners had developed a detailed design for major attacks on the North, but at that time, President Lyndon B. Johnson and his advisers feared that the public would not support an expansion of the war. .
An incident in the Gulf of Tonkin served to justify escalation of the U.S. effort. On Aug. 2, 1964, an American destroyer in international waters involved in electronic espionage was attacked by North Vietnamese torpedo boats. Unharmed, a second destroyer joined it and on August 4, the ships claimed that both had been attacked. Evidence of the second attack was weak at best and was later found to be erroneous, but Johnson ordered retaliatory air strikes and went before Congress to urge support for the Tonkin Gulf Resolution. This gave the president broad powers in responding to attacks on American forces and that served as the basis for the subsequent increasing involvement of the United States in the Vietnam War. This resolution was a virtual blank check to the executive to conduct retaliatory military operations.
In February 1965, after a Viet Cong attack on U.S. Army barracks in Pleiku, the United States commenced Operation Rolling Thunder, a restricted but massive bombing campaign against North Vietnam. Protection of air bases then provided the rationale for introduction of 50,000 U.S. ground combat forces, which were soon increased. The American public, however, was not told when their mission and tactics changed from static defense to search-and-destroy, nor was it asked to bear the war's cost through higher taxes. Desiring both "guns and butter," Johnson dissimulated, ultimately producing a backlash that full public and congressional debate at this point might have avoided. The public never fully supported a war whose purposes were deliberately obscure. All of this was caused by, President Johnson and Congress wanting to be involved in then Vietnam War.