A 2014 survey conducted by the Pew Research Center in which Americans were asked to rate how they felt about various religious groups found that atheists tend to be rated coldly. In fact, atheists averaged merely one degree warmer than Muslims, with 40% of participants rating atheists in the "feeling thermometer's" coldest part and members of religious groups rating atheists more negatively in general.
While hardly surprising, such results are rather puzzling. After all, one would be hard pressed to point to instances of discrimination, oppression, or terrorism perpetrated by atheists in the name of atheism. It's much easier to locate instances--and indeed patterns--of such behavior perpetrated by religious people in the name of their religion (both in today's world and throughout history). There are also no sanctified atheist texts or atheist traditions to inspire or outright command such objectionable behavior, and one is very unlikely to find an atheist in jail or on a most-wanted list that was driven there by atheism. Moreover, like the members of other groups, atheists are generally good people. They are certainly not the demons that some religious people have made them out to be. So why, then, do atheists tend to receive the cold shoulder from their religious fellow Americans?
The survey did find that participants tended to rate atheists more coldly when they didn't actually know any atheists, showing that inexperience with what atheists are really like plays a role here. However, even those who knew atheists still rated them as neutral on average, so inexperience with atheists cannot completely explain the lack of warmth felt towards them.
Instead of speculating on what else might be involved here, I will give 3 reasons why religious Americans should warm up to atheists.
1. Atheists are generally good people.
I already mentioned this above, but it is worth reiterating: like the members of other groups, atheists are generally good people. Like others, they care about being good and try to be good. They care about truth, justice, freedom, and the welfare of others. They are good friends, devoted spouses, loving parents, honest and dependable co-workers, and more.
2. Atheists make for good Americans.
Though people will disagree on exactly what it means to be a "good American," I hope we can all agree that a good American must care about the rights and liberties of American citizens. Not just one's own rights and liberties, but those of everyone. Not just those that one has a personal interest in securing and protecting, but each and every one that ought to be secured and protected. And atheists are likely to care very much about the rights and liberties of their fellow Americans. They will certainly not deny other Americans their rights and liberties in the name of any religion, and since they believe that this life is the only one that we get, they are likely to care a lot about the freedom that their fellow citizens have to make the best of it. They are even likely to care about the ability of religious Americans to freely practice their religion.
3. Atheists are valuable for religious conviction.
This probably sounds crazy. After all, don't atheists represent a rather extreme threat to religious conviction? They do indeed, yet this is precisely where their value lies. For each and every atheist serves as standing encouragement for religious people to stay in touch with the rational grounds of their religious convictions. Just knowing that there are other rational beings out there that disagree with them so fundamentally should encourage religious people to reflect upon their reasons for their religious convictions. It should also encourage them to remember that there are reasons on the other side that deserve serious consideration. One's religious convictions will not be rational if these other reasons are simply ignored, or if they cannot withstand rational reflection on these reasons. Nor will such convictions be rational if they are not based on good reasons to begin with. Atheists are valuable for religious conviction, then, because they serve as standing encouragement for religious people to hold such conviction in the way that they surely want to hold it: rationally.