Except that you don't build walls on your neighbor's property!They don't complain about egypt/gaza, saudi/yemen, saudi/iraq, or anywhere else where walls are used to protect and keep out undesirables. Even the US has a wall between them and mexico. When no walls there are fences to separate.
Israel, like other nations, builds her fences where they will most effectively save lives ... and it has. I can see how this is a major thorn in your side. Should the Arabs choose peaceful coexistence the fence can be removed.
http://www.nytimes.com/2007/09/05/world/middleeast/05mideast.html