One day after Hezb'allah leader Hassan Nasrallah announced that "We will be the ones who bring victory" to President Assad's forces battling rebels in Syria, two rockets were launched from outside of Beirut that struck a Shia neighborhood. The area is under the control of Hezb'allah.

In that speech yesterday, Nasrallah acknowledged for the first time that Hezb'allah milita were fighting in Syria. It has been known for more than a year that Hezb'allah was engaged in massacres of civilians and kept an eye on Syria's largely conscript army, shooting anyone in the ranks who didn't carry out orders to attack innocents. But Nasrallah appears to be going for broke, seeing Assad's survival as vital to maintaining the terrorist group's position in Lebanon.

Reuters:

Syria's two-year uprising has polarized Lebanon, with Sunni Muslims supporting the rebellion against Assad and Shi'ite Hezbollah and its allies standing by Assad. The Lebanese city of Tripoli has seen frequent explosions of violence between majority Sunnis and its small Alawite community.

French Foreign Minister Laurent Fabius condemned the violence in Lebanon. "The war in Syria must not become the war in Lebanon," he told reporters in Abu Dhabi on Sunday.

Kuwait, which like several Gulf states warned its nationals last year against visiting Lebanon, urged any citizens in Lebanon to leave and reiterated its advice not travel there.

Until recently, Nasrallah insisted that Hezbollah had not sent guerrillas to fight alongside Assad's forces, but in his speech on Saturday he said it was fighting in Syria to defend Lebanon from radical Islamists now leading Syria's rebellion.

Hezbollah forces and Assad's troops launched a fierce assault last week aimed at driving Syrian rebels out of Qusair, a strategic town close to the Lebanese border which rebels have used as a supply route for weapons coming into the country.

Lebanese authorities, haunted by Lebanon's own 1975-1990 civil war and torn by the same sectarian rifts as its powerful neighbor, have sought to pursue a police of "dissociation" from the Syrian turmoil.

But they are unable to prevent the flow into Syria of Sunni Muslim gunmen who support the rebels and Hezbollah fighters who support Assad, and have struggled to absorb nearly half a million refugees coming the other way to escape the fighting.

No one has taken responsibility for the rocket attack and Hezb'allah has been ominously silent on who they will blame. This is important because if they blame domestic enemies, it will give them an excuse to strike back. This kind of tit for tat is very dangerous in Lebanon which has experienced Shia-Sunni clashes in the streets, especially in the city of Tripoli, over the last several months. It wouldn't take much at this point for violence to explode into the kind of militia warfare that led to 15 years of civil war in the late 20th century.

Hezb'allah dominates a weak government and can pretty much do whatever they wish. But these attacks could be a game changer. The more Hezb'allah becomes involved in their neighbor's civil war, the more likely the rebels will fight them in Lebanon.

And Israel would be trying to deal with two nations in chaos on its borders.