Like everyone else in the region Hizbullah is waiting for the day after President Al-Assad's departure, writes Graham Usher in Beirut Last month the Lebanese army arrested 18 armed men and confiscated a warehouse full of guns in Tripoli, Lebanon's second city. The raids brought to a temporary close a bloody turf war between a Sunni militia opposed to Syria's Bashar Al-Assad and an Alawite militia which views him as a protector. Seventeen people were killed and 120 injured in what was perhaps the worst outbreak of sectarian violence in Lebanon directly attributable to the war in Syria. For many, Tripoli revived the memories of their own 15-year long civil war, and fears of Lebanon once again becoming the theatre for other people's conflicts. There were also fears of a confrontation between the government and Lebanon's Shia Hizbullah movement, the country's most powerful political and military force, and a strong ally of the Al-Assad regime. The 18 men belonged to a clan with ties to the movement. Yet Hizbullah made no protest about the arrests. Such quiescence had been foreshadowed by Hizbullah's response to the arrest on 9 August of Lebanon's former Information Minister Michel Samaha. An associate of Al-Assad and one time ally of Hizbullah, he allegedly confessed to plotting bomb attacks against Lebanese religious and political figures sympathetic to the Syrian opposition. This tinder for a sectarian conflagration was supposedly mixed with Syria's National Security Chief, General Ali Mamluk and, by some accounts, President Al-Assad himself. On 11 August Hizbullah MP Mohamed Raad said the charges sounded "suspicious", a sentiment in which he was hardly alone. But Hizbullah has distanced itself from Raad's comments, implying that it thinks the government has a case. What gives? For some analysts Hizbullah's sudden coyness is because the Lebanese government has finally authorised the army to get tough with it, seeing the movement as weakened by its pact with a declining Syrian regime. Observers in Lebanon say dream on: the Lebanese state is as weak and fragmented along sectarian lines as ever. Hizbullah's current pivoting has less to do with its position in the Lebanese government than with the question that has defined and circumscribed its politics during the 17-month long Syrian uprising: how to maintain its regional axis with the Al-Assad regime while preserving the support of key political and sectarian constituencies as a Lebanese national movement at home. It is no easy walk. Everyone knows Hizbullah will not cut its ties with Damascus, say Lebanese analysts. Not only would such a rupture threaten its supply lines to Iran. It would wreck a relationship that has been central to Hizbullah's rise as a regional power. It is because Al-Assad for the last decade let Hizbullah operate freely in both Lebanon and Syria that it has become the Arabs' most powerful military force against Israel. "Hizbullah has a moral obligation to stand by Al-Assad," says an observer. Yet Hizbullah's alliance with Al-Assad has cost it much in the region. Seven years ago -- after its 33-day war with Israel -- most Arabs viewed Hizbullah as the region's premier resistance movement. Today it is seen increasingly as a lackey of Shia Iran and/or an apologist for a blood soaked Syrian regime that is killing its own people. Even in Hizbullah there is the view that Damascus has failed as a state. The movement appears to have no strategy for the regime's survival -- only for its demise. Like every other player in the region Hizbullah is planning for the day after Al-Assad goes. In the meantime, it has one overriding goal and several red lines, say sources. The goal is for Hizbullah to translate the military kudos it enjoys on the ground into the legitimacy of a democratic mandate in the 2013 parliamentary elections. For this to happen it needs to act to ensure that the erosion in support it has seen abroad is not duplicated at home. Hizbullah must win back its core Shia supporters not with bombast about resistance or Al-Assad but through a government that creates jobs, delivers services and provides security. It must also preserve its hegemony as Lebanon's premier military power. In relation to Syria there are three principles, say sources. First, Hizbullah will resist any attempts by Damascus, Saudi Arabia or anyone else to export Syria's sectarian conflict to Lebanon. Some in Hizbullah apparently saw the clashes in Tripoli as a crude attempt to drag it into such an imbroglio. It refused the bait. Second, the government -- and only the government -- will be empowered to deal with any spillover from the war in Syria, whether it is in ending the fighting in Tripoli or sorting out the consequences of the arrests of Samaha or Hizbullah aligned gunmen. In all cases -- at least publicly -- Hizbullah will defer to the government. Third, and most fundamental, Hizbullah will do everything it can to make sure Lebanon doesn't descend into civil war as a result of sectarian differences sharpened by the conflict in Syria. Such a fall would risk everything the movement has achieved in Lebanon since its founding as an Iranian offshoot in the early 1980s. On such bases Hizbullah believes it can survive the end of the Al-Assad regime, even though it knows that will leave a Middle East more hostile to resistance movements like itself. The danger is the more the Syrian regime falls apart, the more it and others may stoke the sectarian fires in Lebanon. And at a certain point Hizbullah may no longer be able to play the fireman. That point may have already been reached, according to one reading of Hizbullah leader Hassan 's gnomic speech last month. Nobody "controlled" Lebanon, told his followers, including Hizbullah. "Reconsider the idea that says there is a definite situation in Lebanon that is under control. Let everyone assume his responsibility," he said.