OK, suppose you think that religion really does harm, and we really have to do what we can to stamp it out. Most of us don't have the opportunity to help establish or eliminate religion by the use of violence. But suppose an opportunity arises. Through a violent act, we can, as we see it, greatly decrease the influence of religion on the world. Now what do you do? Do you say "No, violence is wrong, we have to let the God delusion die of other causes. The end does not justify the means." or do we say "OK, yeah, we're doing violence, but this is how we vastly decrease the influence of religion on the world. The end does justify the means."
The Grand Inquisitors, the prosecutors at the Salem Witch Trials, the Crusaders, etc. all thought that they were doing good and promoting the kingdom of God.
In Tolkien's writings, the moral fate of many of the characters depends upon their willingness or unwillingness to use power (such as the power of the Ring) to do what they perceive to be good. What possible reason do we have for believing that atheists, especially of the Dawkins variety, would resist the use of power and even violence to promote atheism if the opportunity would arise? I can't think of a single one.