I don't really mind either one much. The truly dangerous ideology in America is moderatism. It slows down progress.
Yes, extremists have been so good at bringing about progess.
No, I don't mean "centrist" people. My definition of a "moderate" is somehow who votes based on superficial reasons, but refuses to admit it to himself.
But I will point out that most positive things were extreme once. Such as abolition, black people getting civil rights, women's suffrage, etc.
Although after seeing the sex gap on the 2004 election results, I'd be okay with killing off that last one.