RKL,
I think the fact that the Israelis vehemently deny that they have nukes and aren't afraid to use them to turn several, if not all Arab et al, capitals and large cities into glass parking lots, have done more to stay the hand of the Arab nations arrayed against Israel.
Sadat and Egypt made peace with Israel for piles of US Cash.
Jordan did it for money as well, trade and piles of US Cash.
The former Iraq, and the rest of the Arabian peninsula now just make anti-Israel noises to keep the screaming beards happy. Lots o' business being done on the QT between them.
Syria lives in fear becoming the largest and nearest glass parking lot.
Iran is run by the screaming beards, hence their whole "peaceful" nuclear project, which if their allowed to complete will produce a butcher's bill like the world has never seen.
History has shown that liberal democracy's tend not to attack one another.