Read the excerpt from a speech about the war in vietnam given by president johnson in april 1965.

"the world as it is in asia is not a serene or peaceful place. the first reality is that north vietnam has attacked the independent nation of south vietnam. its object is total over this war—and all asia—is another reality: the deepening shadow of communist china. the rulers in hanoi are urged on by peking. this is a regime which has destroyed freedom in tibet, which has attacked india, and has been condemned by the united nations for aggression in korea. it is a nation which is the forces of violence in almost every continent. the contest in vietnam is part of a wider pattern of aggressive purposes.”

—president lyndon johnson, april 1965

what is the most likely reason president johnson involved the us in the conflict between north vietnam and south vietnam?

he hoped to build a more peaceful world.
he wanted to stop the spread of communist ideas.
he wanted to free the people of tibet from chinese rule.
he hoped to form an alliance with vietnam to attack china.