Socialism, communism, progressivism, nazism, modern liberalism and fascism are all just variations on the theme of economic and social central planning by a government with too much concentrated power. They are all just different branches on the tree of totalitarian leftism. The difference between them is like the difference between cow manure, bull manure, horse manure, dog manure, pig manure and elephant manure. Its all basically the same thing.
I use Coke and Pepsi to describe the difference between nazi/fascism and communism but I like the manure example much better.
I think this is a good argument because liberals believe wholeheartedly that far left is communism, and the far right is Nazi/fascism/Conservative. Nothing is further from the truth. Ask them how you can have Fascism without total government control of the people (just like communism)
Draw this chart and explain it, I did to a liberal friend and her head exploded.
I keep this on my home page:
<<<<<<<<<<<<<<<<<<<<<<<<<<<<<< GOVERNMENT CONTROL <<<<<<<<<<<<<<<<<<<<<<<<<<<<<<
Communist->Fascist->Liberal->Democrat->Moderate->Republican->Conservative->Libertarian->Anarchist