It's hard to overstate the importance of Hezb'allah's intervention in the Syrian civil war. The Lebanese terrorist group had never deployed beyond the borders of their tiny country, and by joining the Assad regime in trying to squash the rebellion, they are gambling that their help will be a game changer.

That may be coming to pass.

Reuters:

Syrian forces and their Lebanese Hezbollah allies seized control of the border town of Qusair on Wednesday, dealing a strategic defeat to rebel fighters battling for two years to overthrow President Bashar al-Assad.

Assad's upturn in fortunes could further diminish hopes of concessions at a peace conference the United States and Russia are seeking to convene, with Damascus increasingly confident of success against a ragtag opposition that is short of weapons.

A member of a pro-Assad Syrian militia said the military focus may now move to the northern province of Aleppo, which has been largely in rebel hands for the last year.

Bolstered by his Iranian and Russian backers, Assad's forces have launched a series of counter-offensives in recent weeks against mainly Sunni Muslim rebels battling to overthrow him and end his minority Alawite family's four-decade grip on power.

Hezbollah's Al-Manar television showed a man climbing the bullet-pocked clock-tower in the town's wrecked and mangled central square to plant a Syrian flag.

"We will not hesitate to crush with an iron fist those who attack us. ... Their fate is surrender or death," the Syrian armed forces command said in statement. "We will continue our string of victories until we regain every inch of Syrian land."

A Hezbollah fighter told Reuters the town had fallen in a rapid overnight offensive, allowing tanks and troops to roll into the rubble-strewn streets after dawn, with many buildings in the city center reduced to mounds of twisted concrete.

Outgunned rebels said they had retreated from Qusair, which lies on a vital cross-border supply route with Lebanon, after two weeks of fierce battles that marked the Shi'ite Hezbollah group's deepest involvement yet in Syria's civil war.

As a proxy for Iran (whose military is so decrepit that it would have trouble intervening decisively even if they wanted to) Hezb'allah is gaining new found respect in the region and has gotten a political boost at home, where their government has canceled elections this year due to an inability to reach an agreement on a new election law. While it is unclear whether they will intervene in other battles to come, their presence alone gives President Assad a measure of security he didn't have just a few short weeks ago.

The danger is that the rebels may see this too and attack Hezb'allah enclaves in Lebanon, especially southern Beirut and the Bekaa Valley where the terrorist's have their command and control facilities. This could lead to a civil war in Lebanon if Hezb'allah believes the Sunnis and Christians are complicit in the attacks.

If Assad manages to survive, he will preside over a ruined, basket case of a country with millions of refugees, an economy that is literally destroyed, and probably a permanent low-intensity rebellion that will make governing impossible.

Meanwhile, Hezb'allah will reap the rewards of victory, becoming unstoppable in Lebanon and emboldened enough to threaten Israel. Their stature in the Middle East will soar as will their sponsor's, the Iranian government.

The only thing worse might be a rebel victory.