Here is a post I wrote on
Strategypage:
or those of you who have been paying some attention to the Lebanese blogosphere, many are angry that Israel is going after Hizb'allah in Lebanon, rather than Assad in Syria, who is, after all, one of Hizb'allah's patrons. However, they understandly fail to appreciate the military situation. I reference readers to this map, courtesy of Debka:
http://www.debka.com/pictures/Lebanon.jpg
If one looks at where the shortest route from Israel to Damascus is, its easy to realize that is skirts Southern Lebanon. In essence, if Israel were to go after Syria first, it would leave its flank open to Hizb'allah attacks from Lebanon. Israel would probably have no choice but go into Lebanon to attack Hizb'allah positions, so that they can't disrupt the Israeli lines of supply into Syria. In short, Israel would have to deal with Hizb'allah in Lebanon if it wanted to go after Syria.
This means it makes as much sense for Israel to go after Hizb'allah first, before going after Syria. One consequence of this means that if Israel does in fact intend to go after Syria, that attack will only come after Hizb'allah has largely been neutralized inside Lebanon, and most likley after large elements of Hizb'allah have fled to Syria. Israel might only intend to deal with Hizb'allah now, but the dicates of the geography of the region and military necessity meant that whichever strategy Israel takes, it is indistinguishable from the other.
The actual post can be found
here.