You're not wrong about how polarization is tearing down our democracy. Specifically, what you're describing is the culture wars. The rightwing of conservatism in America has morphed into a party of fearmongering, anti-democracy culture wars. Yes, there is an extreme left – but they are actually the tiniest minority in the political landscape. It wasn't the Democrats or even the extreme leftwing who assaulted the Capital with the intent to stop democracy.
The GOP would have you believe that every single person not in their extreme right camp is AntiFa or communists – that includes those conservatives the label "RINOS" like Liz Chaney. Now, I disagree with almost every policy Liz Chaney ever supported. She voted 95% of the time with Trump's agenda. She has always been a right of center-right conservative. However, I have never doubted her dedication to our consitutional democratic republic. Today's Trump GOP is demonstrably anti-democracy.
I actually registered as a republican after I turned eighteen. But, I thought I was registering for the party of the 1956 GOP platform, in 1980. Naive of me… yes? I was slightly right of center at that time. I genuinely did not move very far left. I would say that I am now left of center for what was center in the 1980s. But, the GOP has moved so far right, that where I am now is considered by them to be extreme.
In the minds of Trump's GOP and constituency: It's extreme to want Gender and Racial equality; to want economic equity and full bodily sovreignty. It's extreme to not want to force a ten year old to have her rapist's baby. It's extreme to want billionaires and mega corporations to pay their fair share of taxes. It's extreme to want to police the endlessly repeating police brutality. It's extreme to want healthcare access for everyone in America without individuals facing bankruptcy or worse. It's downright unamerican to want to take military-style weapons out of civilian hands; better to leave the armed and armored 376 "good guys with a gun" to stand their ground outside in safety listening to the screams and gunshots decimating children's bodies, then silence for seventy-seven minutes.
America's political polarization is driven by the extremes of what the GOP has steadily become since 2010, with the election of Dominionist Tea Party theocratic corporatist republicans like Ted Cruz. The threats of violence are mostly by the hands of the armed, white-identity MAGA nationalists.
Again: It wasn't the Democrats or even the extreme left who assaulted the Capital with the intent to stop democracy.
