The turmoil in Lebanon is approaching the level of danger that preceded its 1975-1990 civil war.

Last week's fighting, which involved Hezbollah, government forces and other sectarian militias, raged throughout the country -- in the capital Beirut, Tripoli in the north, the Chouf mountains and the Bekaa Valley. It claimed at least 44 lives.

It is another struggle along sectarian lines, including Shiites, Sunnis and Christians, for control of the government. It pits the authority of Sunni Prime Minister Fouad Siniora and his allies against Shiite Hezbollah and its allies. The crisis includes the inability of the Lebanese parliament to elect a president, an office that has been vacant since November.

Hezbollah has grown in strength and aggressiveness in Lebanon since it resisted Israel's attempt to extirpate it in 2006 through an invasion. All Hezbollah had to do to win then was survive, and it did. Now it is trying to grab a much larger role in Lebanese governance, taking advantage of the Shiites' position as Lebanon's largest minority and itself as their leader in Lebanon.

The United States backs Mr. Siniora's government and has pledged to strengthen the Lebanese Army. The army, which did not play a decisive role in last week's fighting, is divided inside itself to some extent. Lebanon's Christian minority, according to the constitution, provides the president, but the Christians are divided among themselves, which is one reason for the failure to choose.

Syria and Iran back Hezbollah. The Arab League, partly at U.S. instigation and partly because it is basically an organization of Sunni Muslim states, has sent a mission to Lebanon to seek a resolution of the current conflict. Its prospects are limited. Syria's foreign minister did not attend the Cairo meeting that sent the mission and most of the elements in the Lebanese struggle don't care what the Arab League thinks.

The United States can do nothing except watch, or perhaps place some Navy ships off the coast of Lebanon. It has no relationship that would permit dialogue with Hezbollah, Iran or Syria, and U.S. military intervention would be folly. Israel is in no position to even consider invading Lebanon again, given its experience the last time.

There are two reasons to hope that a catastrophe can be avoided. First, the resolution of minor issues could head off a general meltdown and, second, Lebanon has been to the brink of disaster many times and achieved a compromise. Cross your fingers.