You just reminded me of something I had forgotten.
Back in the 1990's, before Free Republic was a gleam in Jim Robinson's eye, I encountered a website with an interesting piece of information that would be classified as Conspiracy Theory today. Now I'm not so sure.
The story was that back in the 1980's, the CIA had contracted with Disney to make a short animated film, similar to "Fantasia", titled "The Great Dying". There was no spoken dialog in the film because it was intended for international distribution. It was just animated images and music.
One of the scenes in the film was supposedly of a tide of diseased humanity from Central and South America piling up on the Mexican side of the US border and being forcefully repelled by Americans. The image was of a high wall at the border.
The description of that image came back when I read your post.