USA intervened in Korea and Vietnam as war efforts and in Greece and Turkey as coups.
Step-by-step explanation:
In Turkey the US government aided a coup by the military to overthrow the government which in turn led to a regressive government to be placed in there.
A similar thing happened in Greece when a socialist party was elected into the Country with affiliations or alleged ones with the Soviet Union.
Korea was invaded by the USA in support of the south during the Korean war so as to stop the communist North from taking over all of the Korea under the influence of USSR.
Similar thing happened in Vietnam but it was not successful and Vietnam did fall to the communist army after US departure.