Hezbollah, the radical Islamic organization in Beirut, has devoted the past 20 years to accumulating political power in Lebanon as it provided humanitarian relief to Shiite slum dwellers and staged periodic terrorist attacks against Israeli forces and targets overseas.

Now Hezbollah has abruptly emerged as a major player in the regional military crisis gripping Israel, Lebanon and the Palestinians.

It was Hezbollah's raid on a border station in Israel on Wednesday to kidnap two Israeli soldiers that triggered the aggressive Israeli military response apparently designed to isolate Lebanon from the outside world and pressure Lebanon's weak coalition government to rein in Hezbollah.

Arabic for "Party of God," Hezbollah has long operated an independent militia of several thousand fighters across southern Lebanon where Lebanese armed forces do not patrol. Hezbollah's territorial authority reflects the substantial political power that the Iran- and Syrian-backed organization has built up within Lebanon since its military operations and suicide bombings helped force U.S. withdrawal from Lebanon in 1984 and final Israeli withdrawal in 2000.

Hezbollah is widely regarded in Lebanon and in parts of the Arab world as a legitimate nationalist force that helped free Lebanon from foreign occupation.

"I can tell you (for) a majority of Lebanese, Hezbollah is a national resistance movement," Emile Lahoud, the Christian president of Lebanon, said in 2003. "If it wasn't for them, we couldn't have liberated our land. And because of that, we have big esteem for the Hezbollah movement."

Two of Lebanon's nine government ministries as well as 23 of the 128 seats in Lebanon's parliament are now held by Hezbollah, putting the internationally designated terrorist organization squarely in the middle of governing Lebanon, a strategic Mediterranean nation the size of Connecticut with 3.8 million people.

Hezbollah's civilian arm operates hospitals and schools and provides support for economic and infrastructure projects in Shiite-dominated areas through the so-called "Reconstruction Campaign."

The Israeli air force on Friday apparently targeted Hezbollah's longtime leader, Sheik Hassan Nasrallah, destroying his home and party headquarters in Beirut's teeming southern neighborhoods. Nasrallah responded with a defiant statement directed to Israel: "You wanted an open war, and we are ready for an open war."