Why should Republicans have to put up with hordes of deranged leftists who believe all conservatives are inherently evil Nazi's? Why should white men have to put up with all the racists who believe they're systemically, irrevocably evil by nature, and awaiting the day that all white people can be killed or enslaved?
Diversity of viewpoints doesn't mean every viewpoint is equally valid. It means that we endure the crazies on both sides, and don't let their stupid theories prevent rational conversation and good-natured and loving people from coexisting. That is, we become more mature, and find ways to cool down the hyperbolic rhetoric -- not abandon each other.