While tens of thousands of US troops are fighting the Taliban in Afghanistan, their presence is unwelcome in ally Pakistan and strikes by unmanned aircraft have become the main, if controversial, US combat tactic.
The Long War Journal, which tracks the strikes, says missiles have killed 15 senior Al-Qaeda leaders, and 16 “mid-level” Al-Qaeda and Taliban operatives since January 2008, as well as Baitullah Mehsud, the leader of Tehreek-i-Taliban Pakistan (TTP).
Despite Mehsuds death, TTP are killing more people than ever and Al-Qaeda leaders Osama bin Laden and Ayman al-Zawahiri -- both believed to be sheltering along the Afghan-Pakistan border -- remain at large.
“I dont think the group has necessarily been weakened at all. In fact were seeing more large-scale bombings and attacks in Pakistan than weve ever seen and with a very large casualty count,” said Venzke.
President Barack Obama has ordered 51,000 extra US troops to Afghanistan, hoping to turn the tide in the war and deny Al-Qaeda sanctuary, but tribal experts fear drone attacks could spawn a war of revenge for years.
“The way they are now attacking with their drones, trying to hit local militants -- maybe local militants are not a big threat to America but in the future they could become a threat,” said tribal expert Rahimullah Yusufzai.
The tribal belt is barred to outsiders, communication links are poor and foreign militants are said to impose a reign of fear, making the cost of the drone attacks and their long-term impact impossible to assess.
Local residents contacted by AFP in North Waziristan -- a district where 22 of the last 24 attacks have struck -- said families lived in fear over the prospect of a Hellfire missile annihilating their home without warning.
Yet speaking from Mir Ali, one of the main towns in the district, one shopkeeper said the drones did appear to have deterred foreign fighters.
“There seems to be only one advantage -- the number of foreigners who used to roam markets in the region freely has reduced considerably,” Noor Mohammad told AFP by telephone.
In a tribal belt with widespread illiteracy and few jobs, militants exploit drone attacks to recruit, and there are fears that Pakistans perceived role undercuts its own counter-insurgency campaign against homegrown radicals.
President Asif Ali Zardari, who is massively unpopular at home, has warned that drone attacks undermine national consensus in “the war on militancy” as Pakistan struggles with bombings that have killed nearly 3,000 people in less than three years.
“Drone attacks are radicalising other people who may not have supported the Taliban,” warned Yusufzai.
Lisa Curtis, a research fellow at the conservative Heritage Foundation, said the Obama administration had little choice but rely on drones after the failed Christmas Day plot to blow up an airliner renewed fears of Al-Qaeda.
“The long-term costs are that its raising anti-Americanism in Pakistan, which in turn makes it more difficult for us to cooperate with Pakistan,” she told AFP.
The United States is increasing pressure on Islamabad to take on groups such as the Haqqani network, which attacks US forces in Afghanistan but is reputed to retain links with Pakistani intelligence.
Samina Ahmed, an analyst for the International Crisis Group, said US tactics had yet to spark major protests and cautioned against exaggerating the current impact for the civilian government.
“If there were drone attacks on urban centres, major civilian casualties, there would be a public outcry,” she said. It would become a major challenge to the Pakistan military and the Pakistan government,” she added. -AFP