The majority of communist governments that rose have been the leftist equivalent of fascism though. The two aren't opposites, but practically the same. It doesn't make sense to divide the ideologies by what form of draconian government they become. The real divide are the values that make you go "I belong on this side" or "I belong on that side." To me, the divide is caused by 4 main concerns:
1. The economy
2. Concern for others
3. Individual rights/concern
4. Liberty- specifically in regards to from the government
I think, US conservatives and democrats consider number 3 their hugest tenant, but then apply it according to their prioties.
A democrats' would look like this:
A conservative's like this:
Where a democrat might step on your rights(3) to promote someone else's(2), a conservative will step on your rights(2) to promote their own(3). Where a conservative will sacrifice others and himself(3)(2) for the economy(1), a democrat will sacrifice the economy(1) for others(2). Where a democrat might state the government is stepping on our 4th amendment(2), a conservative will say it's necessary(3). Where a conservative will say the government is stepping on our 2nd amendment(3), a democrat will say it's necessary(2). Obviously, plenty of people don't adhere 100% to this- ESPECIALLY not to the last two examples, but that's how I see the divide between us. Not our D and R politicians, but
us ourselves.
You can't actually use reason to close it, because the divide isn't even a question of whether we should build the house with wood or brick. Few care whether the wood or brick is actually better for the situation. What they actually care about is who's land is going to be sacrificed for the house and who for, so unless you can convince someone that they care for the wrong things, you're not going to make any real progress. It's like the equivalent of trying to convince someone that one art piece is better than another. Objectivity actually begins to get destroyed around that point, and it's just your personality and feelings that are making all the choices.
You see this most heavily in regards to beliefs surrounding rape allegations, because it's as clear as day; Either the land of men will be sacrificed or the land of women will be sacrificed. You legitimately can't partake in those kinds of discussions without feeling at least a bit dirty because everyone loses and you know it.