Israel was taken from the people living there in an arbitrary fashion by the allies after ww2 in order to find a place for all the displaced european jews. Many of whom were trapped on a ship that countries including the us refused to allow to dock. The borders established in the middle east paid no attention to centuries old tribal and religous affiliations and conflicts. The displaced people were forced into a ghetto much like the ones the jews were forced into pre ww2 in europe.
So yea they been bitching ever since.
Those same people were living there under British rule. And if you want to cite Biblical boundaries then there is no doubt Israel belongs to the Hebrews.
It's a shitty situation, but Israel allows Arab citizens and Arab vote. The Palestinian State affords no such luxury to the Jews.