Is atheism worth defending?

After one has accepted the truth of atheism, questions about its value arise. Once you conclude that there probably is no God, then what? Is this fact worth defending? Should atheists even bother to rebut their critics and develop arguments for their positions?

The main reasons why I think that atheism is worth defending are epistemic ones. The first of these reasons is quite simple: atheism is a true or rational belief. As both intrinsically and instrumentally valuable things, truth and rational belief are very important goods; so any belief will be valuable insofar as it is true or rational, and this value constitutes a very good reason to defend it. Other epistemic reasons for defending atheism are constituted by our duties as responsible epistemic agents. As such agents, we have a duty to defend true and rational beliefs for their own sake, as well as a duty to defend true and rational beliefs in order to engender such beliefs in other epistemic agents.

http://www.infidels.org/library/modern/ryan_stringer/value-of-atheism.html

A perfect illustration of shallow atheism.

What if atheism is nihilistic? Are nihilistic truths valuable?

From a secular standpoint, what makes truth “intrinsically” good? What makes anything intrinsically good from that vantage point?

What if nothing is good? What if true and false beliefs are equally harmful? What if, no matter what you believe, you are doomed? 

Why does Stringer assume we even have duties, much less an inalienable duty to defend truth for truth’s sake? Why should we be responsible epistemic agents? What if I’d rather be irresponsible? If I lose either way, what’s the difference?  What if it’s more fun to be irresponsible?

Suppose I’m an atheist. Suppose I’m abducted. Suppose my captor gives me a choice. On the one hand, I can continue to cling to me true or rational beliefs. If I exercise that option, I will spend the rest of my life in a concrete cell with a bare light bulb.

On the other hand, I can take an injection which will cause me to forget my true or rational beliefs. If I exercise that option, I will spend the rest of my life in comfort, enjoying every amenity, under the misconception that this is where and how I’ve always lived.