How does the "Vietnam War" begin?

How did the Communist Party of Kampuchea (CPK) get its name?

Why did Sihanouk start making so many movies in the 1960's?

Time Period Covered 1964 - 1967

In this episode, Lachlan revisits Vietnam as LBJ wages war upon the North and the Viet Cong. Pol Pot leaves the jungle to visit Hanoi, and Beijing, and changes the direction of Khmer Communism. Meanwhile, in Cambodia, Sihanouk begins losing his magic touch as various quarters become less enamoured with his policies. The Cambodian Civil War approaches, as the war in Vietnam begins to spread.

Sources
Philip Short Pol Pot: History of a Nightmare
David Chandler The Tragedy of Cambodian History & Brother Number One
Ben Kiernan How Pol Pot Came to Power
Milton Osbourne Sihanouk
Steve Heder Cambodian Communism and the Vietnamese Model
Edward Miller The Vietnam War
Mark Atwood Lawrence A Concise History of the Vietnam War
Democratic Kampuchea Livre Noir