IMO religion is the biggest threat there is to humanity. It continually impedes the progress of science and peaceful coexistence among people. It is used as a basis to persecute groups of people. It draws in the money and time of the gullible, diverting vast resources from other things. It is far worse than drug addiction. I'm not here to be religious; I'm here to discuss the problem of religion.
To deflect the argument that churches do good things, I will acknowledge such, but I do good things as well. I'm not affiliated with other atheists or agnostics, but I contribute mightily to my community. I don't do this to curry favor with the Great Sky Fairy, but rather to help those who can't help themselves, and to make it a better place for my children to live.