My uneducated thoughts are that because Hamas are too embedded into Palestinian society and have essentially infiltrated every aspect of their government, the correct strategic maneuver is to eliminate the Palestinian government and install another puppet government as a replacement in order to destroy Hamas.
They cannot do this without carte blanche approval from the major world superpowers to invade and target civilians who are involved in Islamic terrorism. The ultimate goal, I believe is to absorb more land into Israel and deny Palestinians Gaza completely by the next decade.