Lebanon has been the scene of several political assassinations in recent years, but this fighting was the worst explosion of sectarian violence in Beirut since the bloody 15-year civil war that ended in 1990. By Friday, 15 Lebanese had died, 50 more were wounded and Hizbullah fighters controlled large swaths of the city, including Hariri’s TV station and the area surrounding his headquarters. The outcome appeared to herald a significant shift in the city’s balance of power. For nearly two years, an uneasy stalemate had prevailed in Lebanon between the U.S.-backed government of Lebanese Prime Minister Fuad Siniora and the Shiite militants of Hizbullah. “Now there is a winner and a loser,” says Paul Salem, director of the Carnegie Endowment’s Middle East Center. “It is a defeat for the U.S. foreign policy, which supports the Lebanese government.”

The latest round of fighting began Wednesday when Siniora’s government moved to shut down a private telephone network operated by the Islamists. Hizbullah supporters blocked roads and burned tires in protest, insisting that the network was critical to the country’s defense. The group’s leader, Hassan Nasrallah, insisted that the move was a declaration of war. Lebanese Army officers, fearful that their forces would shatter along sectarian lines, largely stayed out of the fighting. The military deployed troops and tanks at key intersections but didn’t attempt to take on the better-armed guerrillas. “The fighting took place in front of me,” one Army officer stationed in Ras el-Nabeh lamely recalled. “I saw everything.”

Pro-Siniora politicians seemed to realize almost immediately that they had miscalculated by forcing the moment to its crisis. Saad Hariri suggested that any decisions relating to the phone network be put in the hands of the military—a move widely seen as a face-saving gesture. Still, Hizbullah refused the deal. “Hizbullah wants to control Beirut or most of Beirut and then get a settlement that takes into consideration the new balance of power,” said Ali al-Amin, a columnist for the newspaper Al Balad. “There is a new reality on the ground that will impose itself.” Most analysts agree on that point. “The balance of power has shifted dramatically,” says Salem. “It is odd that the government made such a decision.”

Some analysts speculate that by seizing Beirut, Hizbullah was attempting a strategy similar to that of the Palestinian group Hamas, which took power by force in the Gaza Strip last June. Yet at least so far, Hizbullah has proceeded with more caution, declaring it would hand over some captured territory to the Army as a gesture of goodwill. Nasrallah and other Hizbullah leaders are likely to want to avoid the trap Hamas fell into in Gaza. Hizbullah—which is backed by Syria and Iran—has to be careful not to be “too big in Lebanon,” says Salem. Taking permanent control of the entire city in a high-profile coup would likely draw reprisals from Israel—a scenario Nasrallah would presumably rather avoid.