Mark Steyn and David Frum agree that Ariel Sharon agreed to the Gaza withdrawal as a way of calling the world's bluff. Give the Palestinians a state, which takes that issue off the table, and watch it devolve into an Islamist, jihadist nation. The world will come to agree with Israel that the Palestinians cannot govern a state of their own.
Meryl Yourish disagrees with that assessment:
I think the reasons are fairly self-evident: The Gaza settlements were too difficult to defend, sparsely populated, and unpopular in Israeli and world opinion. Now that they've been dismantled, Sharon can say to the world, "See, we did what you've been asking. Now it's time for the palestinians to stop terror." Once again, Occam's Razor applies. The simplest explanation is often the right one. The minute the Gaza withdrawals were over, Sharon said he'd never give up the major Israeli blocs of the West Bank.
The fact that the Gaza Strip will collapse into chaos will also be blamed on Israel. The world keeps moving the goalposts. First it was, "Gaza cannot be a great open-air prison. Get out of the Philadelphi corridor." Now it's "Israel can't control air and sea access to Gaza. Let them have their airport and seaport, and oh yeah, the Egyptians will guard against smuggling." Except they've already stated that they can't possibly catch all the smugglers. So when the "real" missiles (as opposed to "home-made") start landing in Sderot, and Israel tries to do something about it, the world will screech "Sovereignty! Let Abbas take care of it! You can't invade Gaza again!" and, as I said, we will see a louder world outrage than we saw at the hoax of Jenin.
The world will expect Israel to suck it up as their people are murdered. Then again, they always have. This is a lose-lose situation, but at least Sharon can continue to insist that Israel took her first steps on the Roadmap, and it's the palestinians turn now.