As the Bush administration sought last week to play down Hezbollah's success in boosting its power and legitimacy in Lebanon, the militant group's rising influence around the world has led some intelligence and counterterrorism officials to ask whether the Iranian-financed organization has grown more dangerous to the United States than al-Qaida.
Though few believe Hezbollah would launch an attack in the West, continued hostility between the United States and Iran could significantly raise the threat level here, several former counterterrorism officials and analysts said - especially if the tensions evolve into full-blown conflict.
Compared with al-Qaida, Hezbollah has a far more pronounced posture inside the United States and around the world, analysts and Bush administration officials have said. And while it has not organized an attack against the United States in 25 years, the group had more American blood on its hands before the Sept. 11 attacks than any other terrorist operation - the deadliest example being the 1983 suicide bombing that killed more than 200 Marines in Beirut.
"They are the granddaddy of them all," said Kenneth Bell, a former federal prosecutor who disrupted a Hezbollah cell in North Carolina in 2002, leading to a more than 100-year jail sentence for the group's ringleader. "Hezbollah has the greater infrastructure, expertise and arms to be much more lethal as an organization than al-Qaida."
Some hard-liners have described the Islamist group's activities in Lebanon during the past month as an effective coup, after militants boldly seized much of West Beirut when the government tried to shut down its communications networks.
Nearly 70 people were killed in the ensuing violence before a power-sharing arrangement brokered by Arab nations gave Hezbollah what amounts to veto power over the new government, which selected army chief Michel Suleiman as the country's new president yesterday.
Secretary of State Condoleezza Rice said Thursday that the group hurt its own cause among the Lebanese when its members "turned their arms on its own people," but some analysts and former intelligence officers say that Hezbollah's continued defiance of the West has made it more powerful than ever and a looming threat to the United States.
Last year's highly controversial National Intelligence Estimate predicted as much, noting that the group had concentrated its attacks outside the United States but might consider such an operation if "it perceives the United States as posing a direct threat to the group or Iran."
Most intelligence and counterterrorism analysts credit the group with an extraordinary global presence of several thousand operatives, with cells in Europe, Africa and North and South America. In the United States, the group has limited itself to recruitment as well as fundraising through a variety of illegal schemes, including cigarette smuggling and drug-trafficking.
In addition to the North Carolina cell disrupted in 2002 that was sending cheap cigarettes purchased in that state to Dearborn, Mich., Hezbollah-linked rings have been caught or implicated in Los Angeles and New York, often funneling hundreds of thousands of dollars to the organization through cashier's checks and money orders.
"If it appears that there's a crisis with Iran, we have to be very concerned about Hezbollah agents operating in this country," said Rep. Peter T. King, a New York Republican and ranking member of the House Homeland Security Committee. "There are people under surveillance ... and we are constantly on the lookout through international intelligence and our own to be on our guard against Hezbollah."
"Now that Hezbollah has regained power in Lebanon, it is a strategic extension of the Iranian regime," said Walid Phares, director of the Future Terrorism Project at the Foundation for Defense of Democracies in Washington, who recently provided a closed briefing on Lebanon to congressional staff members. "If we get an escalation of tension with Iran, the Iranians will use Hezbollah against the interests of the U.S. and its allies. They will use the Lebanese republic and the Lebanese diaspora."
One possibility likely to lead to increased tension would be any echoes of the fighting between Israel and Hezbollah that engulfed the country in the summer of 2006.
Claire Lopez, a professor at the Centre for Counterintelligence and Security Studies who teaches a course on Middle Eastern intelligence services, said because of the recent power-sharing agreement in Lebanon, there is "a strong possibility of hostilities breaking out again.
"You almost don't know what could set it off," she said. "In an atmosphere like this, it could be any little spark, any little trigger. ... If Israel responds with strong force, Hezbollah cells elsewhere certainly could be activated for a terror attack mission."