I think i was some thing to do with the soil and sugar or tobacco one of the two?
You mean the Cold War? Containing communism wasn't a priomary goal of World War 2.
Search-and-destroy missions in Vietnam were largely unsuccessful. This is because new and larger reinforcements of Viet-Kongs moved in as soon as American forces departed. As such, these missions did not stem the flow of refugees.
Should be Mekong, because nations like Thailand, Vietnam all have the Mekong running through it