A few reasons:

• Partly just to get some things off my chest. I’m pissed off a lot and need to vent.
• To communicate with the like-minded and bolster their spirits. It’s lonely and isolating to be a non-Christian in America.
• People keep talking about how it’s impossible to change people’s minds. That may be true, but we should be ashamed of it. Saying, “Oh, minds won’t be changed!” is a cop out of the highest order.
• There are realities in the world. But putting the truth out there means nobody can say they weren’t told. Ignorance is forgivable, willful ignorance is not.