At least they're number will decrease if they realize it's pointless.
They're giving the wrong message to all the potential non-muslims who may want to revert by drawing Prophet Muhammad (peace be upon him) in the wrong way.
??... As far as I can see the opposite might happen, besides it only shows how immature they are. I doubt the sincere seekers will buy it. Also, I've read about some reverts who've started searching Islam after seeing anti-islamists' lies.
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