Quote Originally Posted by lakedaemonian View Post
I can think of a couple realistic possibilities:

1.)The void that existed in Northern Iraq that became a somewhat autonomous-ish Kurdistan within Iraq could expand to include a portion of Syria territory with Syrian ethnic Kurds which could cause a growing rift with Turkey which has a long history of conflict in suppressing Kurdish independence in the region including it's own significant and perpetually unhappy Kurdish minority.
Conflict between Turkey and ethnic Kurds would primarily be about Turkey maintaining its present Kurd population within it's borders. The most that could occur would be some sort of a Kurd/Turkish war, which would not develop into a regional conflict involving other countries.

2.)Asymmetric attacks against Israel being launched from Syria/Lebanon as a direct/indirect result of the instability/fall of the Syrian regime and the power vacuum that inevitably follows which would compel Israel to act in proactive self defense.
In the short and medium term, I think a power vacuum in Syria would focus Syrians on the process of filling that vacuum, rather that engendering attacks on Israel. The Syrians would be too busy attacking each other, at the very least politically.

3.)The fall of the Assad regime and/or it's retreat to a smaller and more defensible position leads to sectarian division and potential post Assad civil war and long term instability, much like former Yugoslavia and the rally cry of "someone has to do something" compels intervention.
That would not be a "regional conflict".

4.) Concern over Syria's WMDs(yes I know credibility in this regard is low, but Syria's development/possession of them seems to be well supported) compels some to consider a limited intervention. It must be noted that there are plenty of examples of fairly quite/covert intervention to mitigate WMD risk that have been quite successful.
That would not be a "regional conflict".
5.)The fall of the Assad regime leads to a hard shift that overshoots in the opposite direction towards an islamist/fundamentalist movement/government...much like Iran post Shah.
And the Syrian islamist/fundamentalists invade Israel? Not likely.