If I was Israel and got this 1 week ultimatum I would go ahead and do it. Pull back let them have the land. The first attack that happened afterwards I would go in full bore and take control of the WHOLE of Gaza, not just the part they have now. Then I would go through and wipe out every single person that is suspected of being Hamas. Forget civilian casualties. Then tell the people that "Hey, we will withdraw to our borders one more time. If we are attacked again then we will do just what we did this time and this time KEEP Gaza for our own".