Athiests come out swinging just as much as thiests and on one website specifically designed for a dialogue between christians the christians tend to be much more polite.
In regards to all of the Christians forums which I've been involved, they appear to be polite, but are merely stroking each others delusions. They usually ban the ass of atheists right out of there.
I have sympathy for anger directed at the institution of the church and for people who never seem(ed) to notice all the problems with it, but I can only repeat it is not my experience that online atheists are curious and polite and only lash back.
Religion is a disease spreading through the minds of people that has the capability to ultimately destroy mankind. "Curious and polite" should not be and usually are not characteristics when dealing with diseases.