Complex sentence: Skeptical civilians and journalists are told that multinational Communism is what the U.S. is fighting in Vietnam; proof: weapons and equipment, captured from North Vietnamese soldiers and Vietcong guerrillas, manufactured in the Soviet Union, Communist Czechoslovakia, and Communist China.
Split into simpler sentences: Skeptical civilians and journalists are told that international Communism is what the U.S. is fighting in Vietnam. Proof: weapons and equipment, captured from North Vietnamese soldiers and Vietcong guerrillas, manufactured in the Soviet Union, Communist Czechoslovakia, and Communist China.