The Syrian Ba'athist regime is a hybrid of a political party, social movement, with strong (but not dominant) Shi'ia religious bonds (while ideologically more secular, socialist in outlook than Iran, and Syria is more religiously diverse, the Assad family and many ranking party members still retain a common Shiite identity).
The Ba'ath Party is far stronger than any conceivable coalition of domestic opposition forces that might dare to coalesce to challenge it. Unlike Libya and Iraq, this is not a strongman-centered regime, but is instead, like Iran, a broad-based and cohesive political-religious movement - which makes both regimes natural allies (and rivals), and formidable common opponents. The biggest threat to the Party is the Sunni Muslim Brotherhood, and the fact that Syria is roughly 80 percent Sunni. Efforts at regime change have played off of Saudi-funded efforts to divide and radicalize the local Sunni clergy, which have long been subdued by the secular government and authorities.
The real strength in depth of Syria (like Iran) is its unconventional, guerrilla warfighting capabilities, which cannot be defeated by air power alone, and would require very large U.S. or NATO ground forces to subdue. Israel, alone, could not do it alone using its own conventional forces (despite its air superiority and what is claimed for its advantage with precision stand-off weapons). The following assessment is from an Israeli military publication:
http://defense-update.com/20110913_evolving-into-hybrid-forces-challenging-the-idf-precision-fires-domination.html The change of mind in the Syrian Army came after the 1991 first Gulf War (Operation Desert Storm), where Syria became part of the U.S. lead coalition forces, sending the 9th division to fight the Iraqi invasion of Kuwait along with other coalition forces ( But eluded entering into actual combat). The Gulf War was an ‘eye opener’ for the Syrian high command, becoming exposed to the high lethality of western modern weaponry and tactics, so far being entirely geared to Soviet combat doctrine and its inferior weapon technology. This earth shaking experience triggered Syrian General Ali Aslan, then Army Chief of Staff to begin the transformation.
The strategic shift was not exclusive to Syria. Iran has also implemented a similar move, by gradually expanding its reach and influence in South Lebanon through their Hezbollah proxy. Hezbollah developed its forces as independent fighting units each dug into a specific location, equipped with personnel, weapons, supplies and fortifications capable of operating continuously for days, independent of communications, supply lines or even command and control.
With several such domains dominating key locations in South Lebanon, the small semi-irregular force, trained to fight in virtually ‘hybrid’ style, was deployed to contain an Israeli land maneuver, by posing continuous fighting capability deployed throughout the theater, denying the Israelis the ‘luxury’ in attacking strategic ‘weak points‘ in an attempt to overwhelm the entire enemy array by massive surge operations. Operating such multiple domains in and around the villages and cities of South Lebanon in 2006 enabled relatively small forces of Hezbollah to deny the Israeli army dominating the battle areas, constantly keeping the Israelis at risk, despite repeated efforts to clear certain areas and vital supply routes. What seemed to be Israeli hesitation and indecision was actually an unsuccessful attempt of the northern command to seize the initiative pushing the enemy off balance.
The IDF could employ different land maneuver campaigns. One option was a deep, decisive push north, through the enemy interior, in a move that would isolate the battle area and eliminate any escape of Hezbollah northward, weeding out enemy forces by exposing their hideouts. Alternatively, a series of local operations, closer to the border, could methodically wear out enemy forces by a series of local engagements, backed by massive support fires from the Israeli side of the border, exposing minimal forces to enemy attack. Both concepts were partly tried in 2006, without much success, using insufficient force concentrations, and failing to apply continuous pressure, due to political hesitation.
The different concepts have inherent drawbacks. The deep penetrating maneuver required massive forces to go simultaneously after all enemy hideouts throughout the combat area, including locations bypassed during the initial move, in a highly organized and closely controlled operation that would seep up large IDF forces and risk significant casualties and collateral damage. On the other side, the ‘local’ alternative would not help in eliminating rocket attacks on the Israeli rear area, which inevitably raises a political issue, questioning the overall purpose of the campaign from a national viewpoint.