1945
From the beginning, the US involvement in Vietnam was confusing. After World War II, The French Nationalists wanted to hold on to the Laos, Cambodia, and Vietnam territories. The French wanted to keep them for Rubber, Cork, Food Products, and Money. Vietnam wanted independence just like the US fought for and won from England. 1945, Nguyen Sinh Cung (who would later be known as Ho Chi Minh) started the Democratic Republic of Vietnam. He fought a Guerrilla War where by day they were farmers and at night they would put on their guns and fight. We sent the OSS (the equivalent of today's CIA) to train Ho Chi Minh's troops in Guerrilla fighting because we believed he wanted Vietnam to be democratic.
1950
At first the Civil War in Vietnam was between the French Vietnamese and the US backed Vietnamese who were working with Ho Chi Minh. In 1950 The United States realised that Ho Chi Minh was actually a communist when a photo of him reading Carl Marx's manifesto became public. At that point in history we hated communism more than anything and gave $15 Million to the French and switched sides. We continued supporting the French and over the next 4 years gave them $3 Billion dollars. Now the war was the Viet Minh who supported communism V.S. The Vietnamese army supported by the US and France.
1954
On May 7th 1954, Viet Minh beat the French Army so badly that they surrendered and signed a peace treaty called the Geneva Accord. This caused the country to be split in two at what was known as The 17th parallel. Ho Chi Minh was now the leader of North Vietnam and Ngo Dinh Dien was the leader of what became known as South Vietnam. The civil war and US conflict continued.