How, why, and when did US involvement in Vietnam begin? How did US involvement change with each president from Truman to Nixon?

The Vietnam War started in the 1950s, according to most historians, though the conflict in Southeast Asia had its roots in the French colonial period of the 1800s. The United States, France, China, the Soviet Union, Cambodia, Laos and other countries would over time become involved in the lengthy war, which finally ended in 1975 when North and South Vietnam were reunited as one country. The following Vietnam War timeline is a guide to the complex political and military issues involved in a war that would ultimately claim millions of lives.

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