The recent events in Beirut pose a simple, fundamental question: Who rules in Lebanon? The answer proposed by Hizbullah last week is that the government of Fuad Saniora and Saad Hariri is to be permitted to hold the formal reins of administration - on condition that they well understand the inherent limits of their position. Most important, any attempt to interfere with the Iranian-created and Iranian- and Syrian-sponsored military infrastructure in the country will result in a swift, disproportionate and bloody response. Hizbullah and its backers have made clear that if the choice is between civil war and accepting limitations on the autonomy of their military infrastructure, they will choose the former. At the same time, their actions in Beirut last week made clear that as long as this point is accepted by the March 14 government, they will permit a return to the former stalemate. Recall the sequence of events: Lebanon has been locked in a standoff between the pro-US March 14 Movement and the pro-Iran and pro-Syria opposition ever since the latter launched a campaign to achieve veto power over government decisions, in the months following the war of 2006. The Saniora government refused to bow to the opposition's demands. The result has been ongoing political tension punctuated by periodic flare-ups, such as that of January 2007, which have brought the country to the brink of civil war. The latest tension emerged from a Hizbullah-sponsored series of labor union protests. But the key event precipitating Hizbullah's military takeover of West Beirut was the decision by the government to act against Hizbullah's independent military infrastructure through two bold moves: First, the government sought to dismiss the security chief at Rafik Hariri International Airport, Wafiq Choukair, who is known to be close to Hizbullah. This move came after prominent March 14 leader and Druse strongman Walid Jumblatt revealed that Hizbullah had installed surveillance cameras at the airport's Runway 17. The runway overlooks the hangars containing private jets, an air force base, and the VIP visitors building. Jumblatt further argued that Iranian flights to Beirut should be stopped, as they could be carrying equipment for Hizbullah, and called for the Iranian ambassador to be expelled. In a second, related move, the government launched a judicial investigation into the Iranian-built independent telecommunications network maintained by Hizbullah. This network is thought to extend from Beirut across the south of the country, and into the Bekaa. For Hizbullah, these actions by the government clearly trespassed beyond a red line: namely, the tacit acceptance by the Saniora government that the means by which Hizbullah and its backers conduct their activities in Lebanon are off-limits to the organs of the Lebanese state. The response was swift and furious. Hizbullah gunmen poured onto the streets of West Beirut and engaged the untrained pro-government Sunnis who sought to oppose them. Eleven people were killed and 30 were wounded in the subsequent fighting, which ended with the surrender or flight of the pro-government elements. Hizbullah simultaneously carried out a series of acts designed to humiliate the government and to demonstrate its ineffectiveness. Hizbullah men blocked the roads to and from the airport, cutting Lebanon off from the outside world, forced the pro-government Al-Mustaqbal TV station and other pro-government news outlets off the air, and burned the offices of the Al-Mustaqbal newspaper. The headquarters of Saniora and Saad Hariri was besieged. Following this demonstration of strength, Hizbullah expressed its willingness to hand all captured areas over to the Lebanese army. The message was clear. The events of the past days are an attempt by the pro-Iranian regional alliance to guard the perimeters of its main asset in Lebanon - namely, the well financed and trained Hizbullah military infrastructure. Iran wishes to maintain this structure, but not to seize formal power in Lebanon. Rather, it is an instrument to be activated against Israel, at the appropriate moment. In the meantime, Teheran and Hizbullah are content to leave the Saniora government to continue the administration of Lebanon's internal affairs, on condition it understands its limits. The first question now is whether the Saniora government is prepared to accept this situation. (The original dispute over the dismissal of Choukair and the closing of the telecommunications network remains unresolved.) The second question is whether, if it is not, March 14 possesses the will and the tools to mount an effective opposition to the Hizbullah state within a state. Hizbullah's latest action brings the movement closer to openly pitting Lebanon's Shi'ites against its Druse, Christian and Sunni communities. The opposition's Christian component - the Free Patriotic Movement of Gen. Michel Aoun - appears largely an irrelevance in the developing dynamic. Instead, the allies that matter to Hizbullah now are the Shi'ite Amal movement and the small pro-Syrian and Palestinian militias that have mobilized to support the opposition in the past days. Egypt and Saudi Arabia have expressed support for the Saniora government. The Sunni mufti of Lebanon has harshly condemned Hizbullah's actions. But it appears that Hizbullah feels strong enough to contemplate such a situation, and to dismiss the possibility of the coalition of communities backing the government mounting an effective response. The coming weeks will show if Hizbullah's confidence in this regard was misplaced. The writer is a senior research fellow at the Global Research in International Affairs Center, IDC Herzliya.