Juan Cole outlines a theory that has been rattling around in my head for awhile. Go read it. It's very interesting.
The short version? Rumsfeld and Israel have been planning the Israel attacks into Lebannon for some time as a part of "cleansing" the middle east of terraists and pushing back Iran, unbeknownst to the idiot king Bush. Go read the whole thing .... it's quite compelling and will make you go .... mmmmmmmmm.