Which theory did four u. s. presidents use to justify u. s. participation in the vietnam war?
domino theory
solitary confinement
bridge against communism
monopoly theory

The theory that American presidents used to justify US participation in the Vietnam War was the domino theory.

Explanation:

The Domino Theory established that if a country entered a certain political system, it would drag others from its area towards that same ideology.

During the Vietnam War, framed in the context of the Cold War, this theory was used to predict what would happen if South Vietnam fell against communism.

how did justinian contribute to the byzantine empire?

one famous byzantine emperor was justinian i. justinian ruled from ad 527 to 565. belisarius was the commander who led these armies in an attempt to win back the old western roman empire. the war effort to take back the western part of the empire forced justinian to raise taxes on the people of the byzantine empire.

explanation:

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