ab, why should I not challenge a belief or idea (whatever it is) that I don't hold? Would you say the same thing about, say, a political belief?
You are equally free to challenge a belief that I hold and that you don't, e.g. that god's do not exist. You would not be attacking me as a person, only the belief I hold.
People have rights; ideas and beliefs don't. All ideas and all beliefs can be questioned and such questioning, or challenging, is not an attack on any person: it's an attack on a belief or belief system. Criticising a belief or an idea is not ramming anything down anyone's throat. It's just explaining why one disagrees.
Just as it would be in a political discussion, or one discussing something else, like one's preference for certains foods over others.
Spmeone being argumentative about atheism doesn't hurt me. The most it can do is make me think about what other people believe. I think that's the same when someone is argumentative/challenging about theism and all its associated ideas.
Faith may not be an idea, but it is certainly something based on ideas, just as atheism or one's political stance is. All those ideas, yes, all of them, are up for challenge and discussion, and none of that challenging or discussing is an attack on people.
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