Yes it is. It's against Theism and is not dogmatic, but is still a belief system nonetheless. Some Atheist's follow Dawkins and Hitchens like they are Jesus, which is ironically frightening when you think about it
Hitchens is an outcast from atheist communities and Dawkins in generally just seen as a dick making a buck off of stating the obvious. Hitchens is anti-Islam because he is anti-Islam. He enjoys being prejudice because he sucks at life, the man is a total alcoholic. It's not atheism that made him so hateful of Muslims, being an ass hole is what makes him that way.
There is a huge difference between poking fun of Islam or hating the fictional ideas in Islam (the religion) because of what it causes to happen to people, and hating Muslims (people).
I say it like this.
I hate smoking. I think smoking is stupid, actually it's damn near retarded. I will never smoke and I'm raising my child to not smoke. But that doesn't make me hate smokers,
it makes me hate smoking
because the idea of it is stupid. I can well believe that people who smoke are doing something dumb/harmful but not hate the smokers. Them being people trumps them doing stupid things. One couldn't really value life and be mad at smoking for it causing deaths of smokers if they did not first already care about the smokers as people. Otherwise them killing themselves slowly wouldn't matter, for then smoking would just be killing smokers and smokers are worthless because they smoke, you see the illogical thinking there? You can disapprove of the act and not condemn the whole and every other action done by a person, without any conflict.
That is how I see Islam, Christianity etc. Fucking childishly stupid ideas, but that doesn't mean you bomb the lot of them. If humanity isn't already one of your ideals then you can't really be upset at what organized religion does to humanity. Dehumanizing the religious for them dehumanizing the non religious is just hypocritical. Hate the faith not the faithful. People can change, most of them have been brainwashed since they were children. Have some compassion or at least understanding. Every practitioner has their own spin on the stupidity but as people they all differ from one another and religion is not the main contributing factor. A dick will be a dick, and a dick who is religious will make sure his god is a dick too and practice his religion the same way. A nice person will try to make their religion nice too and back up what they already wish.
The problem is a dick whose make a dick version of religion and can with other dicks of the same ilk and thus create organized assclownery with all the other assclowns.
An Atheist is pretty much an island to themselves. You can't herd cats.