Not really much irony here.
1st) Repubs do the same thing. At least part of the reason repub talking points are so eager to identify Obama as "socialist" is to make that unflattering connection to Hitler, Stalin and Soviet Russia.
2nd)I've never heard anyone, lib or con, claim Kim Jong Il is a hero of theirs
3rd)The appeal of Castro and Chavez is very limited, nonetheless their human rights violations don't even begin to approach the atrocities committed by Hitler
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And then scream and howl if someone has an Obama sign with a picture of Hitler.
See point number 1