LONDON - Al Qaeda's new chief Ayman al-Zawahri may struggle to rally his embattled militants after the killing of Osama bin Laden on May 2 and the simultaneous capture by US forces of some of the group's innermost secrets. The Egyptian-born ideologue and plotter is expected to want to launch a big attack to cement his authority over the far-flung network, which staged the Sept 11. 2001 raids and other bombings on Western targets around the world. In a June 8 eulogy, Zawahri promised to avenge bin Laden, pouring scorn on the US decision to bury his body at sea, a choice he said showed Washington feared bin Laden even in death. "He went to his Lord as a martyr, he who terrorised America while alive and terrorised it while dead, such that they tremble from having a grave for him, due to what they know of the love of tens of millions for him," he said. Bin Laden was shot dead on May 2 in a US raid on a house in the Pakistani town of Abbottabad. Computers, electronic data storage devices and mobile phones seized in the raid are now being examined by US intelligence specialists. But al Qaeda's ability to stage a big assault like Sept. 11 has been diminished by the killing or capture of experienced commanders over the years, and its message of violence has been hurt by civilian-led Arab revolts against authoritarian rule. And for reasons of personality and background Zawahri could find it hard to emulate the unifying role played by bin Laden, his predecessor and the network's founding figurehead, among the increasingly disparate network. Zawahri's apparently prickly temperament and Egyptian background could make it hard to mediate between the Egyptians who have dominated the upper reaches of the central al Qaeda group and other militants, including nationals of Arab, Asian, African and European countries as well as of the United States. Al Qaeda's leadership has struggled with internal disputes at times, and some arguments over strategy and ideology have been marked by strains based on nationality, historians say. Of particular interest will be Zawahri's relationship to al Qaeda in the Arabian Peninsula, which is based in Yemen, led by a Yemeni and has many Saudis in its ranks. Many are believed to have felt close to bin Laden, who had Yemeni ancestry. "Not a particularly inspiring figure, and one who lacks bin Laden's cachet, it is no certainty that Zawahri can effectively serve as the 'new logo' of al Qaeda," former CIA operations officer John J. LeBeau told Reuters. "As well, despite the announced succession, it is entirely possible that elements within al Qaeda are unhappy with this choice and may militate against it, one way or another." Jeremy Binnie, a terrorism specialist at IHS Jane's in London, said he would be watching the reaction to Zawahri from the network's affiliates, allies and sympathisers. "Zawahri is supposedly not much liked in the movement, while there has been speculation that his leadership could be undermined because he is not from ... Saudi Arabia." Zawahri may also be challenged by the task of shoring up alliances between the core al Qaeda group, which is believed to be based mostly in Pakistan, and local Pakistani militant allies in the Asian country's remote northern tribal regions. These ties are seen as critical to the leadership's ability to remain hidden because the Pakistan groups have the firepower, funds and local contacts to keep their foriegn hosts secure. Fawz Gerges, an al Qaeda expert at the London School of Economics, said no one matched "the stature and charisma of bin Laden, a unifying and beloved figure within the organisation". "Zawahri is divisive and prickly, an intellectual giant among the remaining figures in al-Qaeda but not a rallying figure. He is no force-multiplier." Not everyone agrees that Zawahri is unsuited to be leader. Some analysts are suspending judgment on his suitability for the role until such time as the group's affiliates publish statements of support for him. The wording of those statements may offer clues to his stature in the global movement. Australian scholar, Leah Farrall, a leading authority on al Qaeda, said Zawahri had been widely respected for his role as the second-in-command "despite his somewhat sharp personality". "He is certainly viewed as being experienced and this is important. Al Qaeda does not select leaders on whether they are necessarily the most popular, but on how effectively they do their jobs." Zawahri must also do all he can to ensure security for the group's senior figures, who are believed to be at increased risk of detection and capture as a result of the capture of intelligence at bin Laden's house. Ideology may also prove a challenge. In his recent statements, Zawahri has take pains to praise the Arab revolts, going so far as to recall his participation in civilian street protests early in his own life against what he called Western-dominated rule in Egypt. It is an unorthodox statement for a militant who has long argued that violence was the only answer to Western dominance. Some analysts say a foretaste of al Qaeda's future plotting may have come in a video posted online on June 2 by several senior al Qaeda figures calling on followers to stage their "individual" acts of violence against the West. The video, entitled "You are Only Responsible for Yourself", recalled several attacks by so-called homegrown or lone wolf militants based in the West.