A CIA drone strike in Pakistan’s tribal belt killed Al Qaeda’s deputy leader, Abu Yahya al-Libi, dealing another blow to the group in a lawless area that has long been considered the global headquarters of international terrorism but the importance of which may now be slipping.

The details of his death in Hassu Khel, a village in the North Waziristan tribal agency, remained hazy. And it is not the first report that he has been killed: rumors of his death coursed through jihadi Web sites in December 2009 after a similar strike in South Waziristan that American officials claimed had killed a high-ranking figure in Al Qaeda.

Mr. Libi, who was thought to be in his late 40s, was born in Libya, and during the 1990s he was a member of an Islamist group that sought to overthrow Col. Muammar el-Qaddafi.

His star rose after he escaped from a United States military detention center at Bagram Air Base outside Kabul in July 2005, picking a lock and dodging the prison guards, along with three other Qaeda operatives.

A year later, Mr. Libi released a 54-minute video mocking his American captors — the first of many that would burnish his reputation as a propagandist.

Soon after Bin Laden’s death, Mr. Libi moved up to become Al Qaeda’s deputy, behind Ayman al-Zawahri.

If his death is borne out this time, it would be a milestone in a covert eight-year airstrike campaign that has infuriated Pakistani officials but that has remained one of the United States’ most effective tools in combating militancy.

Libi’s death would be another dramatic moment for an American covert war in Pakistan that has been particularly active over the past year, starting with the death of the group’s founder, Osama bin Laden, in May 2011 and followed up by drone strikes against several senior lieutenants, including Atiyah Abd al-Rahman.

But that very success could, paradoxically, signal a shifting target: as Al Qaeda’s leadership in the tribal belt has been cornered or killed, new efforts to attack Western targets have been mounted by the group’s affiliates in Yemen and Somalia.

While drone strikes offer an attractive short-term tactic against Qaeda militants, they do not present a complete strategy. Until the West tackles Al Qaeda’s ideology, state support and ability to exploit ungoverned space in countries like Pakistan, Somalia and Yemen, you’re not going to defeat the organization.

Mr. Libi’s death also raises questions about the center of gravity of Al Qaeda’s global operations. In 2007, the National Intelligence Estimate, a document produced by 16 American intelligence agencies, declared that the tribal belt had become Al Qaeda’s global headquarters. Yet in recent years, some of the most dangerous plots have come from its affiliate in Yemen.

Umar Farouk Abdulmutallab, the young Nigerian who tried to detonate a bomb in his underwear as an airliner approached Detroit in December 2009, was trained in the mountains of Yemen. Last September, an American drone attack 90 miles east of the Yemeni capital, Sana, killed Anwar al-Awlaki, an American preacher and jihadist recruiter, and Samir Khan, an American citizen of Pakistani origin.

Some American officials consider Mr. Awlaki’s death to be at least as significant, in counterterrorism terms, as the killing of Mr. Libi. Even in death, Mr. Awlaki’s archived exhortations for jihad are considered a potent force.

Still, Pakistan’s tribal belt remains a hub of regional and international militancy. Faisal Shahzad, who tried to explode a car bomb in Times Square in May 2010, said he had received explosives training from the Pakistani Taliban. Insurgent fighters based in Waziristan regularly attack NATO and Afghan forces in Afghanistan and have been targeted by C.I.A. drones. And Mr. Zawahri, the Qaeda leader, is widely believed to be in Pakistan.

But the strikes are intensely contentious among Pakistan’s political and military elite. In April, Pakistan’s Parliament passed a resolution demanding that the drone campaign immediately stop, but the tempo of strikes picked up greatly after negotiations to reopen NATO supply lines through Pakistan to Afghanistan bogged down last month.

Practically speaking, the drone strikes are a big success. But strategically they are a huge loss. They create more polarization, more enemies, and are an attack on our sovereignty. We have always told the Americans that if anyone should carry out these strikes, it should be us.

“Until we tackle Al Qaeda’s ideology, state support and ability to exploit ungoverned space in countries like Pakistan, Somalia and Yemen, you’re not going to defeat the organization.”

BILL ROGGIO, the managing editor of The Long War Journal, on the significance of a drone strike in Pakistan that is said to have killed Abu Yahya al-Libi, Al Qaeda’s deputy leader.

Jude K Mohammad, 23, of Raleigh North Carolina Killed in May 2013 in a Drone Attack

When Jude Kenan Mohammad was about 18 and living in Raleigh, N.C., according to people who knew him, he came under the influence of an older man, Daniel Patrick Boyd, who taught him a violent, radical version of Islam.

Mr. Boyd would be charged in 2009 and eventually imprisoned as the ringleader of a group of North Carolina residents who had vowed to carry out a violent jihad both in the United States and overseas. Mr. Mohammad was also charged, but by then, partly at the direction of Mr. Boyd, he had traveled to Pakistan, where he had joined a group of militants in that country’s tribal area.

On Wednesday, the United States government officially acknowledged for the first time what had long been rumored among his friends in Raleigh: that Mr. Mohammad was killed in a C.I.A. drone strike on a compound in South Waziristan on Nov. 16, 2011. He was 23.

He was one of at least four Americans to have been killed in “counterterrorism operations,” Attorney General Eric H. Holder Jr. said in a letter sent on Wednesday to Senator Patrick J. Leahy of Vermont, chairman of the Judiciary Committee.

Only one of those killed, the radical Yemeni-American cleric Anwar al-Awlaki, was deliberately targeted, Mr. Holder said. The others were killed in strikes that did not specifically target them, he said, including Samir Khan, another young man from Raleigh who had joined the Qaeda branch in Yemen and was killed with Mr. Awlaki; Mr. Awlaki’s 16-year-old son, Abdulrahman, killed two weeks later; and Mr. Mohammad.

American officials said that Mr. Mohammad had been killed with about 12 other insurgents in what the C.I.A. calls a “signature strike,” an attack based on patterns of activity, such as men toting arms in an area controlled by extremist groups. Such strikes have prompted the sharpest divisions inside the Obama administration, with some officials questioning whether killing unidentified fighters is legally justified or worth the local backlash.

After the strike, the family friend said, Mr. Mohammad’s wife, whom he had met and married after moving to Pakistan, called his mother in North Carolina to say he had been killed.

Reflecting the covert nature of the drone program in Pakistan, the F.B.I. had left Mr. Mohammad’s name on its wanted list after his death. An F.B.I. spokesman, Kathleen Wright, said that it would be removed.

While Mr. Mohammad was not directly targeted, he had come under increasing scrutiny by American counterterrorism officials, who said he was involved in recruiting militants for Al Qaeda and the Pakistani Taliban, as well as making videos on YouTube to incite violence against the United States.

“He had risen to the top of the U.S. deck,” said Seth G. Jones, a senior political scientist at the RAND Corporation and former adviser to the military’s Special Operations Command. Mr. Jones said that while in Pakistan, Mr. Mohammad had made contact with five young Virginia men who disappeared from their homes around Thanksgiving in 2009 and turned up seeking to join militant groups. Instead they were arrested and remain in Pakistani custody.

A family friend, who asked not to be named because she did not want to offend Mr. Mohammad’s family, called him “a good kid, but a follower.” His Pakistani father, Taj Mohammad, met his mother, Elena, an American who converted from Catholicism to Islam, in New York in the early 1980s. They lived in Pakistan for several years, but in the late 1990s, Elena moved back to the United States with their son.

Jude Mohammad dropped out of high school but later earned his high school equivalency certificate and attended Wake Technical Community College. He was “a regular around the mosque” in Raleigh and often volunteered in the mosque kitchen to help prepare communal meals, the friend said.

“He’d put food on the back of his bike and ride a couple of miles to deliver groceries to the homebound,” she said.

Later, after dropping out of school, he used drugs and described himself as “lost,” the friend said. “He was looking for a father figure.”

After meeting Mr. Boyd, a convert to Islam who called himself Saifullah, he came to see going overseas to fight as a way to purify himself.

Mr. Boyd, who had trained in terrorist camps in Pakistan and Afghanistan from 1989 to 1992, was later banned from the mosque in Raleigh as a troublemaker. In September 2009, he was indicted with his two sons, Mr. Mohammad and four other men for conspiring to plot terrorist acts at home and abroad.

Among other things, Mr. Boyd was accused of carrying out “reconnaissance” of the Marine base at Quantico, Va., and plotting to stage attacks on service members there.

While he was a fugitive in Pakistan, Mr. Mohammad would sometimes call his American friends and family, especially on Muslim holidays, staying on the phone just long enough to offer a greeting for fear of having the call traced.

The calls stopped after November 2011, the friend said, and the reports of his death began to circulate through Raleigh’s Muslim community.