Christians aren't perfect, and they don't pretend to be. Rarely, though, do you get to see Christians acknowledging that their evangelism is similarly imperfect and sometimes even hurtful to others. That's what makes this site extraordinary. No one who posts at this site will likely give up their faith, nor should they, because of personal failings. But we can hope that they will improve themselves by way of the exercise of publicly acknowledging their imperfections, and perhaps move closer to the good ideals of their faith. If so, I will be the first to say "Good job."
Hat tip to the always thoughtful and empathetic Hemant Mehta. Most of his commenters are more cynical than I am about the site, though. Which leads me to another point -- why are atheists often so "militant" about their beliefs? Why do they direct their fire in particular at Christianity? I've been guilty of that myself from time to time.
I venture to guess that most of the time, the answer is "resentment." A lot of atheists feel like they've been lied to by religious leaders and religious teachings. Many psychologists would be quick to point out that religious is often conflated with parental authority, and indeed this is a very interesting track to explore. But for my purposes, the reaction of a person who uses atheism to rebel against her parents is similar enough to "resentment" that I can comfortably equate the two.
A lot of atheists feel like they've had their time, intellect, and money wasted -- or worse yet, diverted into things they are actually opposed to -- and worst of all, some people have suffered actual abuse administered by or justified by religious authorities.
The apologetics on the website seem to mostly apologize for judgmental behavior. It's easy to see why people resent being judged, especially when they are found wanting, and especially for doing or being something that they truly do not think is wrong in the first place. I share some of that resentment myself; I've been preached to and snubbed enough times for my own lack of faith or belief that I admit of an emotional reaction to running in to that sort of thing again. I find myself avoiding the society of people who I think are likely to engage in that kind of judgmental behavior; perhaps, then, I too am guilty of shunning those who are different from me.
And then there's the whole "spiritual protection racket" that most Christianity is based on. Believe and join us, and God will protect and love and reward you with eternal paradise. Fail to believe and join us, and you will lose God's protection and grace, and be condemned to the perpetual flames and punishment of Hell. There is a strain of evangelism out there, and I'll venture to guess that most non-believers react to it as viscerally as I have, that relies extensively upon the fear of Hell and therefore dwells in lurid detail upon how miserable sinners will be in the afterworld. That sort of thing can really scare little children -- and when I wake up and realize that I was being asked to be afraid of a bogeyman, I resented being treated like a child. (Same thing with Pascal's Wager.)
Most non-believers will, if pressed, concede that most of the people who did this to them did so out of good intentions rather than bad. Most atheists will agree that Christians do and say what they do because they think it is morally good to do those things. But the good intention is not enough to justify this sort of thing, nor should it be. A wrong act done for a good reason is still a wrong act. (A good reason for a wrong act is really only relevant for the question of whether it mitigates the appropriate response, not for whether the act should be condemned.) The point is, a lot of atheists (and non-believers who stop short of calling themselves that) resent the way that a significant number of believers have treated them. For me, it has been evangelism -- the judgmental moralizing of evangelicals -- that has inspired this emotion.
A related question is "why don't atheists direct their resentment similarly towards Islam?" (Or Judaism, for that matter, but Judaism seems to be forgotten in that discussion, and I can't think of a single time I've even heard of a person evangelizing for Judaism.) The answer is, there are fewer Muslims in America and Canada and western Europe. And those Muslims are frequently in the position of being minorities and on the receiving end of similar kinds of treatment themselves, so they tend to not behave the way that Muslims seem to behave in newspaper and television reports of majority-Muslim nations. No Muslim has ever held a scimitar over my head, even in rhetorical terms, demanding that I submit to the will of Allah. That's not to say that there aren't Muslims who would do that, but it's never happened to me. Consequently, I have less resentment of Islam than I do Christianity.