Israel did everything the world leaders told them to do and more
NONE of it worked ... that is why Israel is taking matters into her own hands to deal with these terrorists
I think few if any in the Israeli or Bush administrations expected it to work. But it may have given Israel some high ground in the eyes of the arab world and the europeenies (not that she didn't always have that high ground IMO) in which to facilitate the acceptance of anythign she's having to do now and in the future.
Like I said, just a hypothesis I'm working on.