The US can kill everyone in a compound in Pakistan and get away with it. The Soviets are even more ruthless. Super power status buys an intimidation factor that Israel will never have. I'm sure that Egypt's role in mediating this deal was a good part of why it was ultimately accepted. It is a sign of putting thing like the peace with Egypt ahead of principle.
Police arrest 18-year-old Palestinian suspected in Old City stabbing (Haaretz)