I know the history of the Palestinian / Arab - Israel conflict, likely better than you do, and I do not in any way hold Roger Waters in the highest esteem.  

He's anti-Israel (that's fine, that's his choice), he's anti-zionist (again, that's fine, that's his choice), and he's an anti-semite (that's not fine).

Oh, and if you think the Palestinian Arabs are the sole indigenous inhabitants of the region between the River and the Sea, then you clearly do not know the history of the region.