Fascists are wrong because the imagined past never occurred (like the country song that complains that Coke is a slang shortening for Cocaine - as if there was ever a time when Coke was not a reference to Cocaine).
Communists are wrong because the existence of scarcity guarantees that schemes of wealth distribution cannot solve every social problem.
I have found this most wonderful (if fairly lengthy) article, and thought you would enjoy having it brought to your attention.
It is so good, I think we should include it among the references in the "Politics is the Mind Killer" wiki page. But, before that, I submit it to you, and ask you: is there anything in this article that would warrant its exclusion from this site? I mean, besides the fact that it is about politics, and written by a notorious Social-democrat (And is that in itself grounds for exclusion?).