WASHINGTON - - The Bush administration's tacit support for Israeli military strikes on Lebanon may have increased the danger of militant retaliation against the United States and U.S. interests abroad, some experts say.

U.S. and European authorities have stepped up vigilance against groups including Hizbollah, which intelligence experts say has cells in North America, South America, Europe, Africa, Asia and the Middle East.

Israel's attempt to cripple Hizbollah in Lebanon may have strengthened the Shi'ite organization by winning it fresh political support among moderate Arabs and Muslims, former officials and other experts said.

The Bush administration's stance that calling an immediate ceasefire would not be productive has also angered many Arabs at a time when bombings in Lebanon are causing large numbers of Muslim civilian casualties, they added.

Washington argues it is supporting long-term efforts against terrorism in the region.

One European counterterrorism official said it was widely recognized there that Middle East hostilities could become a motivating factor for Sunni groups inspired by Osama bin Laden who ordinarily dislike Hizbollah but might try to exploit the outrage in Arab communities.

"Even al Qaeda itself may be ready with an attack, and they may choose to use it now," said Michael Scheuer, a former CIA counterterrorism official who ran the agency's bin Laden unit.

But Peter Brookes of the Heritage Foundation, a conservative think tank, said the Middle East crisis had not increased the already tangible danger of attack. "We've always been a target, and Hizbollah already has American blood on its hands," Brookes said.

Growing Danger

Some former intelligence officers were adamant about a growing danger, however.

"There will be revenge attacks," said one former U.S. official, who remains up to date on counterterrorism strategy.

"The concern now is that there's rising animosity that will be exploited, not just by Hizbollah," said the former official, who spoke on condition of anonymity, adding: "Then there are people being driven over the edge by what's happening, who aren't necessarily members of any group, but who might strike."

Hizbollah had roles in a number of attacks on American targets in the 1980s and 1990s, including the 1983 barracks bombing that killed 241 U.S. Marines, Navy personnel and Army soldiers in Beirut, according to the State Department.

But intelligence officials said the group was believed to have suspended hostilities against the United States in the 1990s and said there was no sign Hizbollah had changed its policy.

Hizbollah leader Sayyed Hassan Nasrallah has made no threats against the United States in a recent series of speeches and media interviews.

Intelligence officials also said there was currently no evidence of an imminent attack by Hizbollah or any other militant organization.

"That said, you can't rule it out and people aren't ruling it out," said a U.S. counterterrorism official.

Hizbollah has long supported Palestinian militant groups. In 2004, it signed an agreement with Hamas for joint attacks on Israel, the State Department said.

Scheuer said this would be extraordinary opportunity for al Qaeda to emerge as "the champion of the Palestinian people."

The United States could face spontaneous violence soon from local Islamist groups inspired by al Qaeda, or well-planned attacks over the longer term by professionals from Hizbollah or al Qaeda, former intelligence officials said.

"It takes time to prepare a terrorist attack and we're watching closely. So far no one's seen anything, but it's not likely they'd see a lot if an attack is being planned by professionals," one former officer said.

Additional reporting by Mark Trevelyan in Berlin.

© 2006 Reuters

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