I had 24 hour CQ duty last week and ran across this documentary. It is over 4 hours long and is rather dated. It was broadcast in the early 1980s. However, many of the survivors and movers and shakers of the conflict were still alive and able to tell their side of the story.
One of the things that will confuse most people right away is the different definitions for such terms as "Republican", "Nationalist", and so on. However, the varied and diverse kinds of political groupings should look very familiar to most of us.
There were unique political and social situations to the Spanish at the time, however, it does not require great leaps of logic to see similar situations here in the United States. If you do not have the time to watch all of the documentary, just do some research on the Spanish Civil War of 1936-1939 and see what you think.