Wednesday’s announcement of an easing in diplomatic and trade relations between the U.S. and Cuba lit a Roman candle beneath Cuba-related stocks, even as it ignited fireworks of a U.S. political debate. Nine of the top 10 holdings of closed-end Herzfeld Caribbean Basin Fund (CUBA) leapt 2% to 7%. The diplomatic shift should benefit companies doing business in Cuba, says Tom Herzfeld, co-manager of CUBA.