Why did the United States go to war with North Vietnam?

(could somebody right a short summary to explain why? This is NOT for a scratch pad assighnment I just would like a little summary about why the US went)

https://www.google.com/search?q=why+the+US+went+to+war+in+Vietnam&oq=why+the+US+went+to+war+in+Vietnam&aqs=chrome..69i57.8388j0j8&sourceid=chrome&ie=UTF-8

Read several of these search results. Then if you want someone here to look over what YOU WRITE, post it.

Thank you for the link(s), As I clarified this is NOT an assignment I just wanted to know why they went to war with north Vietnam.

The United States went to war with North Vietnam primarily due to the spread of communism and the policy of containment during the Cold War. After the division of Vietnam in 1954 into Communist North Vietnam and non-Communist South Vietnam, the North Vietnamese government under Ho Chi Minh sought to reunify the country under communist rule. The United States, fearing that the spread of communism would threaten its interests in Southeast Asia and beyond, became increasingly involved in supporting South Vietnam, both politically and militarily. As the conflict escalated, the United States believed that defeating North Vietnam was essential for containing the spread of communism in the region. This led to the deployment of American troops, heavy bombing campaigns, and a prolonged and costly war that lasted from 1955 to 1975. The war ultimately ended with the withdrawal of U.S. forces and the reunification of Vietnam under communist rule.