Let's expand on this, because it is crucial to the understanding of the fundamental viewpoints different people hold.
Anti-Theism is not Gnostic- or Agnostic-Atheism, not by definition. In practice, it can be found as a viewpoint many of either category hold close to the chest, but it is not exclusive.
Someone can actually hold a belief in a Deity, and still "practice" Anti-Theism.
One should be able to easily understand the someone might believe in a God (of any sort), yet also reach the conclusion that religion in of itself is dangerous and must be vanquished from mankind if we are to progress.
This is ultimately where we need to go, imho. People can have [a] personal God(s), but it should remain just that - no organization, no cultural distinctions, no group-based religious practices and holidays, etc etc. That is to say, religion is out of the public mind entirely, save for idle chitchat, drunken banter and musing. I thoroughly believe this is what mankind needs, along with a more unified global society (preferably, one with a "global government" that, at the minimum, provides equal representation and decision making for every individual territory. We're too tribal/territorial to truly maintain independent civilizations yet continue to interact with the global community at large. It's impossible to continue this approach while maintaining our fundamental human nature - one of them has to give if we're to truly make any further progress (and not regress), and I don't expect we'll defeat our genetics and behavior anytime soon.
Sorry to take this that direction, but it was to showcase the importance of accurate definitions and which ones are involved when arriving at certain deductions (or convictions).
The vast misinformation on Atheism is at the very heart of the average anti-Atheist bias and thus decides how some Theists view Atheists in such a negative light. It's greatly misunderstood, which is also holding back the progress of Enlightenment.

:awe: