Yes they did. They did give an ultimatum. Its foolish to think na tanan civilians mapull out. Some leave, some will always stay (out of necessity or support).
Hamas' charter calls for the eradication the State of Israel. That pretty much is clear ngano in conflict sila. Now for a Palestinian political party whose agenda is the very destruction of the State of Israel, I would say klaro pud why Israel reacts the way it does.