Even though there are a significant amount of fundamentalists who would argue otherwise, I think most people do have doubts about their own religious beliefs at times. Maybe not lasting doubts or ones to cause them to break away from their beliefs, but there is doubt, curiosity, and speculation. Despite my beliefs, I'm not saying that should people never examine why they believe what they in. I think, like many people, that we can agree to understand, but disagree on matters of religion, even if it's your belief that religion itself is the most destructive aspect of human society.
Yet when it comes to non-religious opinions, be it political matters or personal feelings, nearly all people, even those who claim to be open-minded, have the following mindset:
I believe what I want to believe and I don't want you to challenge it, and I don't want to understand your opinions.
So why is this? Nearly every person believes he or she is right, which is understandable, but why be so dismissive of the possibility of being wrong? Why are one's ideals a cornerstone of faith, rather than something to be debated? Why don't you want to communicate, so that we can agree to disagree, instead of shouting at each other and the more powerful of the two having his or her say based on status?