Yes, a fuzzy but persistent and pervasive extremism--mostly from the Left but the Right cannot fully escape that characterization either--has so changed American culture that we are in serious danger of losing it altogether.
That is where I would take issue. The Left see the extremism as mostly from the Right. But it is no wonder it is seen differently, because as I said there is a cultural chasm.
One problem is the various media programs are bipolar. Confirmation bias abounds. At this point I see no way out of the extremism.
I posted this on another thread.
If you have a Google account, do not surf the web while signed in even though they say it will be more fulfilling experience for you. They will collect every web site you go to and every product you look at and sell it to scads of ad firms. The browsers, Chrome, Google, and Internet explorer have a direct ability to pigeonhole you and filter your searches to what demographic they think you are. (I use DuckDuckGo.com as a default for every search I do. Non-tracking. Take a look)
To me that is a problem that is widening the left/right cultural divide. If they see you looking at Fox news on youtube, they will focus on conservative sites in any search you do, and promote bias confirmation. Of course a similar thing happens if you watch MSNBC on youtube. If you want an objective view of what's happening in the news, don't sign in and let them know your politics.
I hope I'm not straying too far from the OP topic.
The right however does not control the unions, including the national teachers' union, is mostly unwelcome in academics theses days, is mostly unwelcome in most scientific institutions, is mostly unwelcome in the entertainment industry, does not control ANY of the major social media entities, and is poorly represented among the mainstream media. That gives the angry, vindictive (i.e. extremist) left a much MUCH larger forum and MUCH more power to distribute that anger and vindictiveness than what the more extremist right has access to.
That the right is seen as having any voice at all is pretty remarkable but because so many respond to the values and agenda of the right, that also speaks to its importance in the American culture.
That the Left fails to see, understand, or appreciate that has been affecting results at the ballot box, at least until now. We'll see how it goes in November.
But it definitely has had a negative effect on our culture.
I wonder..does the Left..or the Right...control anything? Influence, sure..I see that. But control? Being widely read..I find all voices are available...for the discerning reader. I think that Wuwei hit the nail on the head..confirmation bias. People today actively seek it..and those who hold power see it as a very handy leash indeed.
BTW..I know..personally..many conservatives in academia--I think that many of the ideals labeled 'liberal' are shared by many conservatives--but they get lost in the wording..and in the fear, valid or not, that they will be mocked by their peers, if it were known. The same holds true for liberals who have conservative leanings..but don't know it.
No one has any time for the pragmatic politician with a heart. He/she are frozen out of the political process....while the panderers and manipulators are celebrated.
As for the voice of the right..one need only look to talk radio and sites such as this..to see that there is indeed a voice and a loud one, at that.
Oh, and the scientific community? Well..my people, as it were..have a lot of outright contempt for those who politicize science..Left or Right. Right or wrong..the far right is seen as anti-science--deniers of fact and outright anti-intellectual. The Left is no better..with half-baked theories being accepted as known fact. Politics in general get short shrift...but I do know conservatives in the hard sciences...but to a man or woman..they accept climate change as real..even though they may argue as to origins. Most of the rest of us are busy thinking of ways to adapt to coming times...how being more important than why.