[FouRRaW]

Hey, i was wondering..   

Why is it that any acid stronger then H₃O⁺ will ionize completely?

attempt:  I'll explain using and example.

   HCl + H₂O ---->  H₃O⁺ + Cl^-

A stronger acid (HCl) would make the reaction run to completion. The conjuate of this (HCl) strong acid would ionize to produce a weak base,( Cl^- ).   This weak base will not accept protons and will not react with the Hydronium ion, H₃O⁺  Causing the reaction to stay on the products side and causing the acid (HCl) to ionize completely.  Therefore H₃O⁺  is the strongest acid that can exist in water.

Or is this correct??

[Borek]

You are not wrong, although I don't have a feeling that you are right

Think in terms of water abundance and how it influences equilibrium when there is strong acid present and when there is weak acid present.