Vietnamese Didn't Support the War

   One of the problem that South Vietnam and America had was that the local, indigenous peasants of rural Vietnam did not support South Vietnam's regime and often sided with the Viet Cong, who were South Vietnamese rebels fighting for the Communist North. The history with this problem goes way back to the French colonialism in the region and the French-Indochina War, as well as the Geneva conventions that decided to split the country into North and South. 

The South's government- "More of the same"

   France's fight against Communist rebels in Vietnam known as the Viet Minh, who were led by Ho Chi Minh, was largely financed by the United States, who paid for nearly 75% of the war. Already, this got America off on the wrong foot in the minds of Vietnamese people. When Vietnam won the war against France, Ho Chi Minh was considered a hero, which made people look up to him. However, Vietnam was split into North and South "temporarily" in 1954 into a Communist North and the American-supported South. Many of the leaders in the new South government were in the colonial government which had oppressed the people.

"...Military capability alone cannot solve all the problems in Vietnam..." Robert McNamara, 1964

Ngo Dinh Diem- "The best of a bad bunch"

     The Americans picked a man named Ngo Dinh Diem to be the President of South Vietnam without elections. He was a Roman Catholic in a vastly Buddhist country. Soon in his Presidency, he had any suspected Communists or Nationalists captured, imprisoned and executed.  While 16,000 American military advisers were in South Vietnam, he had all government jobs given to Catholics and family members. Diem even outlawed the Buddhist flag and officially dedicated the country to the Virgin Mary, having the Vatican flag fly at all big events.  This made many Vietnamese distrustful of their government.
A monk commits suicide in protest against South Vietnam's government

The Buddhist Crisis, and Diem's assassination

     When the Buddhist flag was outlawed, a crisis ensued with huge protests and many monks committing ritual suicide. Diem had the government ransack the local pagodas because "they were hiding Communist rebels."  This made the people even more unhappy with the government, and by then, the National Liberation Front had been created, a group of guerrilla fighters supported by the North fighting the South. Diem was only creating more recruits for the NLF, or Viet Cong. In 1963 he was assassinated by his military generals, with three more attempted coups over the next three months. 

"We can help them, we can give them equipment, we can send our men there as advisers, but they have to win it, the people of Vietnam, against the Communists." John F. Kennedy, 1963

Why the South's government was so unpopular

      Many South Vietnamese peasants believed that the country of South Vietnam was a puppet of the United States, which it was. Their people had been fighting foreign people for their independence for more than a thousand years, and now, a war that they didn't even want was being fought for them by the Americans.  Many South Vietnamese peasants didn't even know the difference between communism and democracy, and sided with whichever group would provide protection. 

When the Americans bombed villages they suspected of sheltering enemies, they would only be producing more and more recruits for the North Vietnamese Army and NLF. With so many American leaders stating the support of the local people was necessary to winning the war, the war was obviously going to be impossible to win.