With the killing earlier this week of Al-Qaeda leader Osama Bin Laden by U.S. forces, speculation is rampant that his replacement will be Ayman al-Zawahiri.

59-year-old Zawahiri has been Bin Laden’s right hand man and is wanted for the 1998 attacks on U.S. embassies in Africa. He is on the FBI’s list of most wanted terrorists, and there is a $25 million reward for him.

But according to a report by the Associated Press on Tuesday, some experts believe that Zawahiri “lacks the skills” required to succeed Bin Laden.

“Zawahiri does not have the charisma, does not have the charm, does not have the spiritual type of leadership,” said former CIA director Charlie Allen.

Anthony Cordesman of the Center for Strategic and International Studies added that Zawahiri “was never a fighter. He was never a charismatic symbol. He never spoke in terms of either religion or ideology in ways which reached out to fighters the way Bin Laden could.”

The report noted that the White House is questioning whether Zawahiri will indeed take over for Bin Laden and is in fact speculating that significant infighting may take place within Al-Qaeda for the leadership post.

AP noted that the U.S. is still hunting for Zawahiri and is hoping to glean some information on his whereabouts from the trove of documents retrieved during Bin Laden’s capture.

Meanwhile on Tuesday, the White House released new information about the circumstances of Bin Laden’s capture.

White House spokesman Jay Carney told reporters that Bin Laden was “unarmed” but “resisted,” noting that “resistance does not require a firearm.”

Carney also corrected an official’s statement Monday that Bin Laden’s wife was killed, saying that “a woman” who had been with Bin Laden in the room was shot in the leg after rushing the U.S. assaulter, but was not killed.

The operation to kill Bin Laden has put the spotlight on Pakistan. While it was originally believed that Bin Laden had been hiding in war-torn Afghanistan, he had in fact been hiding in a mansion located only an hour’s drive away from the Pakistani capital of Islamabad.

Pakistan is the second largest world-recipient of US aid. $1.5 billion were appropriated by Congress in 2009 for economic and developmental purposes, in order to gain support in the strategically situated country for the war in Afghanistan against Al-Qaeda and the Taliban. Speculation is that some countries may now cut off the aid to Pakistan, particularly if it is discovered that Pakistan knew about Bin Laden hiding out in its territory. Pakistani president Asif Ali Zardari has denied this.