"Americans" aren't the ones redefining anything though, we are discussing these things in the
context of American politics. There are obviously different levels of extremism and a difference in American right and left politics compared to certain other places or people in history. Behavior from both right and left groups are indeed "extreme" in the context of American politics, in the sense that it is not the norm
here.
extremist
/ɪkˈstriːmɪst/
noun
1.
a person who favours or resorts to immoderate, uncompromising, or fanatical methods or behaviour, esp in being politically radical
adjective
2.
of, relating to, or characterized by immoderate or excessive actions, opinions, etc
http://www.dictionary.com/browse/extremist
As far as the dictionary is concerned, "filling mass graves" is not a requirement to define extremism.
When you try to censor free speech, freedom of expression and police ones thoughts and encourage violence for saying or thinking a certain way, then yes you are being unconstitutional though. Doesn't matter what they agree with, how they go about implementing their beliefs is a different story. I'd also disagree that the two different sides of the left politics here agree on 90-95%, maybe at one time but that ship has long since sailed.
To be honest, I don't really concern myself with how people outside of the USA perceive us since I find a lot of it very skewed to begin with. If you don't live here, then you don't really have an accurate picture of how things really are or how things work. Since it seems obvious that we are never going to see eye-to-eye on happenings and political definitions here in the US and I feel we are just going in circles, I'll have this be my last post with you on the matter and just have to agree to disagree.