That's what they said back in the 1980s. When I was in high school, a retired army general who was a friend of my history teacher came to speak to the class (I can't remember his name). He served with MacArthur during the liberation of the Philippines, so I felt honored to hear him speak. He came a second time to show us a video which was produced by the American Conservative Union, and it focused mainly on the Sandinista regime in Nicaragua and the supposed threat they posed to the rest of Central America. It was the classic domino theory applied to Central America, where they predicted Communism would spread to the rest of Central Mexico, then Mexico, then the United States.
Then I saw the exact same scenario play out a few years later in the movie Red Dawn. (I wonder if the ACU ever got residuals.)
A lot of these countries in Central and South America have been riddled with poverty, deprivation, hunger. Living under the capitalistic militarism of US hegemony has led to military juntas, dictatorships, atrocities. Our government jumped into bed with drug runners like Noriega, who somehow became unreliable and had to be removed. That was an embarrassment.
So, there is a bit of context which has to be mentioned regarding your point about the "importation of Communism." Perhaps from the point of view of those living in those countries (which had already become oppressed, impoverished, and devastated by capitalism), Communism might have been seen as the lesser of two evils, if they ever had to make such a choice.