Atheists are angry, twitching creatures. When faced with the godly they foam at the mouth, wailing and gnashing their teeth. Their sense of moral and intellectual superiority is a fragile thing, easily bruised. They deserve our pity, not our scorn.

This, at least, is the way in which prominent figures in the so-called "New Atheism" movement have been characterised in certain sections of the media. Commentators delight in branding the likes of Richard Dawkins, Daniel Dennett and A. C. Grayling as 'angry' or 'cantankerous' or, worst of all, 'fundamentalist atheist', an oxymoron that betrays a basic misunderstanding of both fundamentalism and atheism.

This is hardly surprising. When backed into a corner, the argumentum ad hominem seems an attractive escape route, even if it involves the imputation of anger where none exists, or the misinterpretation of strong rhetoric as indicative of a lack of objectivity. We saw this in Alom Shaha's review of Dawkins's two-part documentary series The Root of All Evil? for Channel 4, in which Shaha claimed that Dawkins "seems to have chosen a deliberately condescending, patronising and aggressive approach, unnecessarily re-enforcing the notion that scientists are arrogant bigots themselves".

This is a fashionable thing to say, but it doesn't bear much relation to the facts. The worst you can say of Dawkins in these programmes is that he occasionally appears to lose patience with his interviewees (a tendency he has since learned to curb). Aggression can only really be claimed if the dictionary definition is abandoned. Dawkins's rhetoric is no more acerbic than one hears in parliamentary debates, and yet to my knowledge nobody has suggested to Ed Miliband that he should go easy on the invective when deriding Tory policy. Shaha elsewhere berates "the 'angry atheist' brigade". This is another phantom, a projection. Like the 'PC brigade', it only really exists in the minds of the people who deploy the phrase.

It's not a particularly new technique. Take the comic book tracts of Jack T. Chick, an American evangelist who seems to delight in hatemongering in the name of Christ (I was first introduced to his work as a child and, as a devout Catholic, was rather taken aback by the description of the Vatican as the "Mother of Abominations"). Chick's representation of scientists is unflattering to say the least. In one tract, entitled Big Daddy?, we see a lecture in evolutionary biology interrupted by a polite, young Christian student. When the student mentions the Biblical account of the Earth's creation, the lecturer is depicted as visibly sweating and screams the words: "HOLD IT YOU FANATIC!! I could have you jailed for that!!" The sheer lack of subtlety is hilarious.

Of course, Chick is an extreme example, and no thoughtful Christian could take him seriously. But the idea of the intransigent, antagonistic scientist is familiar enough, not restricted to the extremists. It is a commonplace perception based on a false characterisation of atheism that has somehow gained credibility. It is a caricature designed to undermine critics of religion so that legitimate questions can be dismissed as 'sneering'. Moreover, it is experientially unsound. I have never seen any of the 'New Atheists' react with such ferocity. Even when faced with an intellect as unrefined as Bill O'Reilly's, Dawkins manages to keep his cool. And that's quite an accomplishment.

Leaving aside the possibility that, in some cases, anger is a legitimate response (as posited by Greta Christina in her book Why Are You Atheists So Angry?), what interests me is the way in which commentators continue to argue against imaginary foes. A good example is Mehdi Hasan's recent article for The Huffington Post UK, which doesn't so much attack Dawkins as it does 'Dawkins'.

In his article, Hasan restates a number of common anti-atheist arguments, all of which have been successfully rebutted innumerable times by brighter people than me. My concern here is not the obvious weakness of Hasan's arguments, but rather what this article tells us about the misrepresentation of atheists in general. The likes of Christina Odone may call Dawkins a "turkey", and inaccurately describe his views as examples of "prejudice and bigotry", but that's just about the level of sophistication we've come to expect from her. I expect more from Mehdi Hasan.

"I believe in God," he writes. "Shame on me, eh? Faith, in the disdainful eyes of the atheist, is irredeemably irrational; to have faith, as Dawkins put it to me, is to have 'belief in something without evidence'. This, however, is sheer nonsense. Are we seriously expected to believe that the likes of Descartes, Kierkegaard, Hegel, Rousseau, Leibniz and Locke were all unthinking or irrational idiots?"

No, we are not. And no such expectation has been articulated, at least not by Dawkins. Nor has anyone suggested that Hasan should feel "shame" for his beliefs. But what this straw man argument so clearly reveals is a reluctance to engage in the debate properly. Religious positions would be better served if their proponents addressed the actual criticisms, rather than taking a defensive stance against the imagined disdain of those who disagree. Like Robert Frost's drunken cow, they bellow on a knoll against the sky.

Many religious thinkers are happy to concede that faith, by its very definition, is irrational. A dearth of evidence does not pose a problem for faith, it is an inherent corollary of it. And what's so wrong with that? If there are human beings who have no irrational tendencies, I haven't met them. Hasan, however, is loath to make this admission.

What this tells us is that the subjectivity of religious experience can overpower rational instincts in even the sharpest of minds. This is why the religious need to be wary when they participate in this debate. It's clear enough that Hasan wouldn't tolerate such sloppiness in any other realm of discussion. He is fairly damning, for instance, about Sunny Hundal's speculations that the Iranian regime are developing nuclear weapons. On this topic, at least, evidence matters.

But when it comes to religion, Hasan needlessly wrangles over tortuous semantic distinctions between "evidence" and "proof" as a means to circumvent the argument. He affirms that "absence of evidence is not evidence of absence. I can't prove God but you can't disprove him", as though Dawkins hadn't already made the identical point in his bestseller The God Delusion. It is known as the "spectrum of theistic probability", and Dawkins makes it clear that as a scientist he cannot possibly be at the very end of this spectrum as a "strong atheist", but that he occupies the position of the de facto atheist, the belief that there is a "very low probability" of God's existence, "but short of zero".

Dawkins made this very point during a recent interview conducted by Hasan for Al-Jazeera, so it cannot have escaped his attention. Yet in Hasan's recent article it is the imaginary Dawkins who once again takes a beating; he of the frothing mouth and stamping feet who angrily berates the idiocy of his opponents. I'd quite like to meet that man. I'm sure he'd be quite entertaining. Unfortunately, and crucially, he doesn't exist.

The aggressive atheist is not the norm. I fully believe Rabbi David Wolpe when he says he has been bombarded by belligerent emails from non-believers, but the internet is seething with trolls, and these missives can hardly be said to be representative of atheist thought in general. I, for one, have never met a genuinely angry atheist. Should I take it on faith that they exist?

I'm all for having the debate. But let's not have the debate with shadows and ghouls.

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