The referendum was held but many were skeptical about its fairness. Diem rigged the votes, winning a ridiculously massive majority in keeping the South separate
The U.S. looked on in fear, believing that communism would spread like dominoes and if Vietnam fell, it would threaten India, Japan and other nations in that region
The government under US advisement and funding tried to relocate many rural peasants into strategic hamlets to keep them away from the influence of the NLF insurgents but the program was a failure and actually ended up strengthening the NLF
Faced many embarrassments with the spread of communism such as the Bay of Pigs disaster, the construction of the Berlin Wall, and the growth of communist power in Laos. He believed Vietnam was where he could make a strong stand against the spread of communism
Kennedy was reluctant to put US troops on the ground believing that the South Vietnam Army had to defeat the NLF on their own, but they were disorganized, crippled by political corruption, and under constant attack from guerrilla forces
More and more US military advisors and equipment were sent to Vietnam to help, but despite this, the South Vietnam Army continued to suffer silly defeats at the hands of the NLF
Officers of the South Vietnam army rose up against the government and captured the leaders in a coup d'état. Ngo Dinh Diem and his brother and advisor in Ngo Dinh Nhu were brutally assassinated the following day
The u.s. navy ship the USS Maddox was monitoring signals coming from North Vietnam in the Gulf of Tonkin. It fired three warning shots at some North Vietnam torpedo boats who opened fire with torpedoes and machine guns
These incidents were used by President Johnson to order an air strike and get Congress to push through the Gulf of Tonkin Resolution which allowed him to escalate the United States involvement in Vietnam without an actual declaration of war