WASHINGTON — Top American counterterrorism officials today said Al Qaeda is “imploding” and that its violent tactics have turned Muslims worldwide against the organization.

“Absolutely it’s imploding. It’s imploding because it’s not a message that resonates with a lot of Muslims,” the State Department’s coordinator for counterterrorism, Dell Dailey, said.

Al Qaeda still remains the most dangerous threat to America. But of growing concern are organizations like Lebanese Hezbollah and Hamas, which combine social services, local governance, national politics with extremist attacks, Undersecretary of State James Glassman said.

“These are models that have a lot more popular appeal than Al Qaeda, that has almost no popular appeal,” he said.

Vastly more Muslims than Westerners are killed by Al Qaeda car and suicide bombs, particularly in Iraq, where local tribes have largely turned against Al Qaeda in Iraq in the last two years. Extremist violence claimed more than 9,500 civilian victims in Muslim countries in 2007.

American intelligence agencies caution against predicting Al Qaeda’s demise too soon, noting its Pakistan safe harbor and the persistent efforts of its affiliates to conduct attacks in North Africa and elsewhere.

American intelligence officials told The Associated Press in July that Al Qaeda leaders learned from Iraq to temper their local activities to ensure continued access and freedom of movement throughout the organization’s safe haven in Pakistan. The officials spoke on condition of anonymity to discuss sensitive intelligence.

Some hardline religious leaders who once wielded significant influence in Al Qaeda have begun to criticize its violence against civilians, the national intelligence officer for transnational threats, Ted Gistaro, said in an August speech. Mr. Gistaro said Al Qaeda senior leaders have devoted nearly half their airtime this year to defending the group’s legitimacy.

Despite these apparent fissures, Al Qaeda is the most potent threat to America, according to American intelligence officials and reports. A national intelligence assessment released last year said Al Qaeda had regenerated its leadership and ability to conduct attacks in the ungoverned tribal region of western Pakistan.

Afghanistan has grown increasingly violent because of the close ties and collaboration between the Pakistan tribes, the Taliban, and the terrorist organization. Al Qaeda continues to attract new fighters to fight American forces in Afghanistan, and radical Internet sites that provide religious justification for attacks and violent anti-Western rhetoric are spreading.

Mr. Glassman said he is “skeptical” about claims that Al Qaeda is changing its ways, or is even capable of changing its ways.

“The death-cult mentality is part of Al Qaeda’s DNA. An Al Qaeda that could adapt would be a far more dangerous Al Qaeda,” he said.