I’ve written earlier about the 1950s U.S. State Department policy of using jazz musicians as American ambassadors spreading good will around the world in the 1950s, during the cold war (http://blogs.kcrw.com/rhythmplanet/americas-jazz-ambassadors/)
A great example is Louis Armstrong’s trip to Ghana in 1957, shortly after the West African country’s independence from Britain:
A lesser-known story concerns Satchmo’s return to America after the state-sponsored good will mission. The story goes this way: Nixon was on the same plane going into Dulles Airport in Washington D.C.. Vice President Richard Nixon was a big fan, and chatted with Satchmo throughout the flight back from (probably Britain). When they finally landed, Armstrong said he was tired and could the vice president please help him carry some of his luggage. Nixon carried his trumpet case, which was filled with ganja. Armstrong loved marijuana and smoked it everyday, including during his trip to Ghana.
For the record, Snopes has confirmed this account.