Sharon had said that an Iraqi attack on Israel will be met "with every resource" - presumably that means Israel's (widely presumed but never admitted) nuclear armament. If that is the case, Iraq might well cease to exist. One bomb on Baghdad and another on the Iraqi oilfields and after that Iraq just becomes a historical footnotes in editions of The 1001 Arabian Nights.
One interesting scenario for the aftermath of an Israeli nuking of Iraq is the partitioning of what's left of Iraq -- after all, the Iraqis seem very flexible about their geography, having been willing 12 years ago to call Kuwait their new 19th province -- one substantial chunk becomes the new Kurdish homeland (funny how the Palestinians have "inalienable" rights - but only to land after it first is taken by Jews - but not the Kurds), and another substantial chunk becomes the New Palestinian Homeland with all the Moslems transferred out of Israel into this piece of defeated Iraq.