The term anti-theism has been cropping up around the atheist blogosphere a lot lately. It seems like a fairly simple concept at first glance. One who believes that theism is a problem to be overcome could be described as anti-theistic (i.e., someone who actively opposes theism). And yet, the term may also be a convenient way to package some of the factions within the larger secular community.
I am an atheist in that I do not accept the theistic belief claim (i.e., some god or gods exist). Atheism describes my lack of acceptance of this claim and entails nothing else - no worldview, belief system, philosophy, or religion. To be an atheist, I don't have to be 100% certain that no gods exist; my atheism is simply my lack of theistic belief.
But I have many other beliefs that do form a cogent system or worldview. Besides not being a theist, I am convinced that theistic belief is something with which humanity would be better off without. In this way, it would probably be accurate to describe me as anti-theistic because I am opposed to theism. That is, I start with atheism (i.e., I am without theistic belief) and go an additional step whereby I am willing to label theistic belief as a problem in need of solutions.
What I am not, and I want to be very clear about this, is an anti-theist. I am actively opposed to theistic belief but not to religious believers themselves. To oppose theists, as opposed to theism, would suggest that I have given up on them. This is not the case.
I am convinced that the overwhelming majority of atheists are not anti-theistic at all. These are the atheists sometimes accused of not being "real atheists," but this is a mistake. They are every bit as atheistic as the rest of us. Where they part ways is anti-theism. Many adopt a live-and-let live attitude and steer clear of activism. They are not concerned with what theists are doing; they just want to be left alone by the theists. I know this can be a source of frustration to some of us who are also anti-theistic and/or value activism, but it can also remind us that many of our efforts should go toward awakening this group to the perils of theism.
I have not encountered many atheists who would proudly describe themselves as anti-theists, but it would not surprise me to discover that some would do so. They could be a source of energy and drive for the secular movement but might also do harm in the sense that they might confirm many of the "angry atheist" stereotypes. Then again, I am not sure we should be overly worried about our image when we are already one of the most hated minority groups around.
I place myself between these two groups. I am an anti-theistic atheist who recognizes that many theists have tremendous good in them and great potential to be valuable contributors to society. I reject their claim that they would devolve into a mob of degenerates without their god-belief. I think they are better than this. At the same time, I'm not content to sit idly by because I think there is too much at stake. Thus, I recognize that I need to reach out both to theists and to atheists who are not yet anti-theistic.