So, are you making a point here, or just trying to excuse your own bad behaviour?

Why bother telling somebody they are stupid when it's easier to simply ignore them? Stupid people ipso facto have a minuscule attention span and, if not encouraged by response. will get bored and wander off.

That said, the ad hominem attack is never to do with an argument, and is always a failure. Calling somebody stupid is not stating a fact - disagreeing with you does not make them stupid, and an inability to argue effectively in writing or even verbally doesn't either -it's being rude and personal. Why not just agree to differ?

Profanity has its' uses, but is more often a sign of deficient vocabulary than of intelligence. "You're a fucking idiot." is a poor substitute for "You're an unmitigated fool."