Which is the best explanation for u. S. Involvement in the korean war?.

America wanted not just to contain communism - they also wanted to prevent the domino effect. Truman was worried that if Korea fell, the next country to fall would be Japan, which was very important for American trade. This was probably the most important reason for America's involvement in the war.

the doctrine of nullification recommended that states living inside the union have the one-sided, inalienable ideal to void any law made by the national government that could be esteemed illegal.

the united states was shaped based on a general agreement among its individual states. hence, it is inferred that under the hypothesis of invalidation, since the states are the establishment of the union, they have the ability to referee and disprove unlawful laws.