Recently, a religious person asked me if I was happy about being an atheist. I wasn't expecting such a question, and mumbled something along the lines of "I guess so". But upon a moment's reflection, I realized that there's a problem not just with the answer, but with the question. Why should there be any significant emotional content in being an atheist?
Assuming that one is not simply being contradictory or rebellious for its own sake, atheism is merely a logical conclusion based upon available evidence (or lack of evidence). So why should I be particularly happy about being atheist anymore than I should be happy about the sun rising every morning, or that letting go of an object above ground level causes it to fall to the ground? Atheism is just a rational conclusion, and it is probably best not to invest too much emotion into it. There's no particular point in being smugly confident about being an atheist for example, or to be overly pessimistic about a lack of an afterlife. If you're too emotional about atheism, then you're probably believing in it for the wrong reasons, and should re-think why you are an atheist.
In a related point, there is the question of how libertarians "ought" to treat religion. From a strictly technical standpoint, libertarians should be probably be neutral about religion, as long as religion is not an excuse to initiate force or fraud against other people. In short, libertarianism is *merely* a political philosophy, and has little or nothing to say about anything that is not political. A person should thus be free to believe in any nonsense they want to believe in, as long as they are not aggressing against other people.
But if there is no God and no afterlife, aren't religious people perpetuating a fraud against other people? Not necessarily. While there are no doubt some people who are hypocrites or outright liars, and merely use religion as a means of controlling and manipulating other people, many religious people truly believe in the tenets of their religion, and thus cannot be said to be initiating fraud against others. You can't be engaging in fraud if you believe it yourself.
Nonetheless, even though libertarianism doesn't specifically preclude religious beliefs, there may still be a problem with having religious convictions. Libertarianism is essentially just a basic principle, the non-aggression principle, followed through to its logical implications and conclusions. Religious convictions are essentially beliefs held for decidedly non-logical reasons. Thus, while being an atheist doesn't require emotional content, being religious certainly does require an emotional investment on the part of the religious person, and a decided lack of reason and logic to continue to hold religious beliefs.
The mind tends to work hard to justify emotional beliefs, resulting in such things as alleged logic of Intelligent Design, and its supposed superiority over evolutionary theory. And if you can believe in one impossible thing, then why not two, or even, like Alice in Wonderland, six impossible things before breakfast?
The libertarian who holds illogical religious beliefs is thus at greater risk for distorting libertarian views to justify an illogical implication or conclusion. For example, libertarians who believe in immigration restrictions. Admittedly, religious belief is not the only illogical view that puts one at risk for distorting libertarianism. People who believe in the supernatural, UFO's, or conspiracy theories are also exhibiting illogical or irrational tendencies.
Religious people are still in the great majority of the mainstream, however, and religion still strongly influences our society. If you think about it, aren't devout Christians as much a threat, if not a greater threat, to our Western intellectual values and the Classical Liberal tradtion than are believers of other religions, like Muslims? Christians are in a much better position to distort and undermine the culture of science and free inquiry than any Muslim could be. Perhaps Christian Conservatives and liberal hippies are both on the wrong side of the Culture War.