During the 1948 war, they helped the other Arab countries attack by leaving the country so that they wouldn't be in their way and so it would be easier to drive the Jews to the sea. Also, the security fence was put for a reason ! IT was put because of constant suicide bombings ! Had Hamas not sent any suicide bombers into Israel, there wouldn't be a wall !! Every ounce of suffering that comes out of Gaza is Hamas's fault, not Israel !