Atheism is irrational.

[Asmodee]

I could argue that fairies exist.  I could develop some clever arguments to "prove" my point.  What I couldn't do is provide actual evidence because fairies don't exist, so all I would have would be arguments. 

I'd love to hear them   Some demonstrations are better than others. I prefer those that take as given the universe's intelligibility and the efficacy of human reason.

Some other time, perhaps.  I have neither the time nor the will to do anything clever right now.

To the OP, no, it is not "irrational" to not believe that magic is real. 

Define 'magic'. I probably don't believe in that either.

There's no mysterious definition here.  Simply supernatural influence on physical reality.  Any "miracle" in the Bible is correctly labeled "magic".

And your argument, like most of these shit arguments, slyly tries to shift reality, just a little, away from the fact that "I DO NOT ACCEPT that God is real" and toward the fantasy that "I DENY that God is real."  To not accept something is simply to assert that there is not enough evidence to convince you, which is atheism.  To deny something is to assert that there is enough evidence to prove it wrong.  It is a shitty way of lowering the bar for yourself while simultaneously raising it for us.

Your post reeks of incredulity.

Not at all.  If there were any real evidence I would examine it.  I really have no stake in the argument whether or not there is some deity, at least not until AFTER I'm already dead.  But it is a big deal to change my beliefs from "I do not believe any gods exist" to "No gods exist for sure".  Theists often try to slip it by us as if it's no big deal, but it is a VERY big to change my position from disbelief to a positive assertion, from "don't believe in God" to "deny God".