National Review OnLine runs this piece by its editors on the Gaza pullout. No doubt they're largely correct:
It might also be noted that if Gaza becomes a staging ground for terrorist activity against Israel, and it will, of course, then Israel will be under tremendous pressure to turn it into an uninhabited region by evicting the Palestinians. There's simply no possibility that they will allow terrorists to operate from Gaza with impunity and the only way to stop it, short of a costly and probably futile occupation, will be to make it a depopulated zone. The Palestinians are celebrating now, but if they cannot control the radicals in their midst the sweet taste they're presently rejoicing over will soon enough turn bitter.
UPDATE: Charles Krauthammer has written an essay in which he makes similar point. It can be read here.