The domino theory is basically ,if one new country went communist in Asia then it would begin a chain reaction that would cause several more Southeast Asian countries becoming communist. it was the reason the united states went into the Vietnam war. since everyone was becoming a communist no laws were really set so they went into war. As the Vietnam War escalated, America's leaders and soldiers found themselves in a quagmire with no victory in sight. Eventually the war weakened the American economy, divided the people, and eroded the nation's morale.
