By all appearances, the Obama administration wanted him alive, not dead. It posted a $5 million reward for information leading to the "location, arrest, and/or conviction" of Baitullah Mehsud, the fierce leader of the Pakistani Taliban, in a March 25, 2009 notice.
In the rugged mountains of western Pakistan, missiles launched by unmanned Predator or Reaper drones have become so commonplace that some U.S. officials liken them to modern-day "cannon fire." And they are no longer aimed solely at "high-value" targets like Mehsud, according to U.S. counterterrorism and defense officials.
Under a secret directive first issued by former President George W. Bush and continued by Barack Obama, the CIA has broadly expanded the "target set" for drone strikes. As a result, what is still officially classified as a covert campaign on Pakistan's side of the border with Afghanistan has in many ways morphed into a parallel conventional war, several experts say.
Killing wanted militants is simply "easier" than capturing them, said an official, who like most interviewed for this story support the stepped-up program and asked not to be identified. Another official added: "It is increasingly the preferred option."
An analysis of data provided to Reuters by U.S. government sources shows that the CIA has killed around 12 times more low-level fighters than mid-to-high-level al Qaeda and Taliban leaders since the drone strikes intensified in the summer of 2008.
Reuters has also learned that Pakistan, though officially opposed to the strikes, is providing more behind-the-scenes assistance than in the past.
Beyond the human intelligence that the CIA relies on to identify targets, Pakistani agents are sometimes present at U.S. bases, and are increasingly involved in target selection and strike coordination, current and former U.S. officials said.
Back in Washington, the technology is considered such a success that the U.S. military has been positioning Reaper drones at a base in the Horn of Africa.
The aircraft can be used against militants in Yemen and Somalia, and even potentially against pirates who attack commercial ships traversing the Gulf of Aden and the Indian Ocean, officials said.
"Everyone has fallen in love with them," a former U.S. intelligence official said of the drone strikes.
NOWHERE TO PUT THEM
By some accounts, the growing reliance on drone strikes is partly a result of the Obama administration's bid to repair the damage to America's image abroad in the wake of Bush-era allegations of torture and secret detentions.
Besides putting an end to harsh interrogation methods, the president issued executive orders to ban secret CIA detention centers and close the Guantanamo Bay prison camp.
Some current and former counterterrorism officials say an unintended consequence of these decisions may be that capturing wanted militants has become a less viable option. As one official said: "There is nowhere to put them."
A former U.S. intelligence official, who was involved in the process until recently, said: "I got the sense: 'What the hell do we do with this guy if we get him?' It's not the primary consideration but it has to be a consideration."
There are other reasons behind the expansion of the drone program, including improvements in drone technology.
"Many of the highest priority terrorists are in some of the remotest, most inaccessible, parts of our planet," one U.S. official said of why targeted killing has gained favor. "Since they're actively plotting against us and our allies, you've got two choices -- kill or capture. When these people are where they are, and are doing what they're doing, it's just not a tough decision."
The Obama White House chaffs at suggestions its policies could make it harder to capture wanted militants.
"Any comment along the lines of 'there is nowhere to put captured militants' would be flat wrong. Over the past 16 months, the U.S. has worked closely with its counterterrorism partners in South Asia and around the world to capture, detain, and interrogate hundreds of militants and terrorists," a senior U.S. official said.
As the CIA program in Pakistan expands, the Pentagon's own targeted killing programs, run by secretive Special Ops and intelligence units, have also been ramped up under Obama.
"There is little to no pushback" from the White House, according to one defense official who supports the policy. He said that when it came to adding wanted militants to top secret target lists, the Pentagon was getting "all the support it could want," though some insiders think the military isn't updating the lists fast enough.
For their part, U.S. officials say the targeted killing programs have dealt a serious blow to al Qaeda and the Taliban, probably saving American lives in the process.
But as one former intelligence official, quoting Newton's law of motion that every action has a reaction, said: there's no way to know the consequences "upfront."
There are signs that the drone strikes may have become a rallying cry for many militants and their supporters, including Faisal Shahzad, the suspect in the attempted car-bombing in New York's Times Square on May 1. U.S. investigators believe Shahzad received assistance from the Pakistani Taliban, which had vowed to avenge the killing of Mehsud.
Likewise, al Qaeda in the Arabian Peninsula said its plot to blow up a U.S. passenger jet on Christmas Day was payback for what it called U.S. attacks on the group in Yemen.
In a June 2007 debate with his Democratic rivals, then-candidate Obama spelled out why he believed it would be legal to use a Hellfire missile to take out Osama bin Laden in Pakistan even if some innocent civilians would be killed in the process.
"I don't believe in assassinations, but Osama bin Laden has declared war on us, killed 3,000 people, and under existing law, including international law, when you've got a military target like bin Laden, you take him out. And if you have 20 minutes, you do it swiftly and surely," Obama said.
Obama's saber-rattling about using force in Pakistan was a way to "demonstrate his national security bona fides" in the middle of a tough campaign, said Richard Fontaine, a senior fellow at the Center for a New American Security who served as foreign policy adviser to Republican Senator John McCain, who lost to Obama in the 2008 election.
Bruce Riedel, a former CIA analyst, said the Obama administration ran with the drone program because, when it came to office, "it found itself with a real al Qaeda threat and one tool to work with."
"I don't think he (Obama) had really any alternatives. He seized the tool that was in front of him," said Riedel, who chaired Obama's strategic review of Afghanistan and Pakistan policy that was completed in March 2009.
A former U.S. intelligence official said the strategy was "politically foolproof" because the mainstream candidates on both sides of the political spectrum "campaigned on who can kill more of these guys."
Under Obama, the program has grown to such an extent that, according to a Reuters tally, the nearly 60 missiles fired from the CIA's drones in Pakistan in the first four months of this year roughly matched the number fired by all of the drones piloted by the U.S. military in neighboring Afghanistan -- the recognized war zone -- during the same time period.
In Pakistan, the pace has jumped to two or three strikes a week, up roughly fourfold from the Bush years.
Of the 500 militants the agency believes the drones have killed since the summer of 2008, about 14 are widely considered to be top tier militant targets, while another 25 are considered mid-to-high-level organizers.
Independent tallies based on news accounts from the region put the deathtoll from drones since mid-2008 much higher -- at anywhere from nearly 700 to around 1,200.
In addition to authorizing the CIA to strike fighters and leaders linked to Tehrik-e-Taliban Pakistan (TTP), the Pakistani Taliban, Obama's National Security Council recently took the program in a new direction by adding an American citizen to the CIA's hit list -- Muslim cleric Anwar al-Awlaki of Yemen's al Qaeda in the Arabian Peninsula.
The Obama administration says it has safeguards in place for identifying what it calls "lawful targets." A U.S. counterterrorism official said: "Targets are chosen with extreme care... There's no such thing as a random strike."
But some human rights groups question how robust those safeguards could be if the CIA is killing hundreds of militants whose identities are largely unknown. They also worry about civilians.
A Pakistani intelligence official dealing with South Waziristan said the vast majority of the deaths were just foot soldiers. "They hit whoever they get," another intelligence official in North Waziristan said.
A former U.S. intelligence official said it was unclear what protocols the CIA was following for targeting foot-soldiers: "If it becomes a more generalized 'kill anybody' (approach), it degrades the notion we're going after serious threats to the United States. It's a slippery slope."
According to U.S. intelligence estimates, no more than 30 non-combatants were killed alongside the 500 militants -- the equivalent of a little more than 5 percent, or about one out of every 20. These mainly included family members who live and travel with the CIA's targets.
The CIA won't disclose how it verifies who's who among the casualties, but former officials say drones will linger overhead, in some cases for hours after each strike so the CIA can literally count the bodies.
To determine who is a civilian, the CIA looks at a number of indicators, including gender. As a general rule, a woman is counted as a non-combatant, former officials said.
The Pakistani intelligence officer in North Waziristan said 20 percent of total deaths were civilians or non-combatants, or one in five.
But others put the figure much higher. "The ratio is getting better but based on my military experience, there's simply no way" so few civilians have been killed, Jeffrey Addicott, who served as the senior legal adviser to the U.S. Army Special Forces, the Green Berets, said of the U.S. tally.
"For one bad guy you kill, you'd expect 1.5 civilian deaths" because no matter how good the technology, "killing from that high above, there's always the 'oops' factor," he said.
'KILL THEM WHEN THEY'RE EATING'
To justify its extensive use of drones in targeted killings, Obama administration lawyers poured over reams of legal opinions and findings. They pointed to precedents as far back as World War Two, when a squadron of U.S. fighter planes tracked and shot down the airplane carrying the architect of Japan's surprise attack on Pearl Harbor, Admiral Isoroku Yamamoto.
"In a different time and place, that action might have been seen as unchivalrous or unsportsmanlike," Conrad Crane, director of the U.S. Army Military History Institute, said of the 1943 targeted killing.
Like technology, battlefield norms "change by year, change by culture," Crane said. "But taking out enemy leaders is an important part of warfare and has been going on for millennia."
In a recent speech outlining the Obama administration's position publicly, Harold Hongju Koh, the State Department's legal adviser, said: "The United States is in an armed conflict with al Qaeda, as well as the Taliban and associated forces, in response to the horrific 9/11 attacks, and may use force consistent with its inherent right to self-defense under international law."
Scholars say Obama's targeted killing doctrine appears to be little different from Bush's: Once someone has been deemed a lawful target, the CIA has no obligation to warn or seek to detain that person before attacking, said Kenneth Anderson, professor of law at American University.
Other human rights lawyers argue that even in an armed conflict zone, individuals may be targeted only if they take a direct part in fighting. Outside armed conflict zones, they say, international law permits lethal force to be used only as a last resort, and only to prevent imminent attacks.
The United States officially bans "assassination" under Executive Order 12333, issued by President Ronald Reagan on December 4, 1981, but Koh said "the use of lawful weapons systems ... for precision targeting of specific high-level belligerent leaders when acting in self-defense or during an armed conflict is not unlawful, and hence does not constitute 'assassination.'"
Mary Ellen O'Connell of the University of Notre Dame Law School said: "We just don't have the right to bomb people where there's no armed conflict," drawing a contrast between Pakistan and Afghanistan, where U.S. forces are waging a nearly nine-year-old war.
Even if militants use Pakistan as a staging ground for Afghan attacks, O'Connell said the sovereign boundary between Pakistan and Afghanistan must be respected.
"The United States is not fighting in self-defense against Pakistan. We do not hold Pakistan responsible for cross-border incursions into Afghanistan and may not, lawfully, use military force in Pakistan in response to those incursions," she said.
Addicott, the former legal adviser to Army Special Forces, disagrees: "The battlefield in the 'war on terror' is global and not restricted to a particular nation. As in World War Two, there are no national limitations or boundaries. This is war and we are entitled to kill them anywhere we find them."
"We can kill them when they're eating, we can kill them when they're sleeping. They are enemy combatants, and as long as they're not surrendering, we can kill them."
Killing senior militants has its drawbacks. Chief among them is the loss of intelligence that could be gleaned by capturing and questioning them.
In secret documents from 2007 that were recently made public, then-CIA director Michael Hayden highlighted the value of capturing al Qaeda leaders. In an agency document, Hayden details how al Qaeda lieutenant Abu Zubaydah became "one of our most important sources of intelligence on al Qaeda" after his March 2002 capture.
Among other things, he helped U.S. authorities identify Khalid Sheikh Mohammed as the mastermind of the September 11 attacks, whose interrogation, in turn, led U.S. authorities to other high-value targets plotting attacks on U.S. soil.
"It is a balance, a difficult balance," a U.S. military official said. "There's no doubt about it, (targeted killing) impacts your ability to gather first person intelligence. But it has other beneficial effects like removing (leadership) capabilities."
Riedel, the former CIA analyst now with the Brookings Institution, said drone strikes were effective at killing but "the real homerun is taking a senior leader prisoner who, in the course of debriefing, leads you to other senior people and opens the door to a greater insight into the enemy you're facing."
"It's a Catch-22. What do you do with these guys? It's a real policy dilemma which the Obama administration has yet to address," a senior U.S. government official said.
In addition to the closing of Guantanamo, Obama has committed to transferring responsibility for detention facilities to the Afghan government.
Another senior U.S. government official cited the arrest in Pakistan of the Afghan Taliban's top military commander, Mullah Abdul Ghani Baradar, as an example of the constraints on the CIA now that its secret "black site" prisons have been closed.
Though Baradar was nabbed in a joint operation with Pakistan's ISI intelligence service, giving the CIA custody was never an option. Baradar has started talking but the U.S. government official said the information flow would be greater were he held in CIA custody.
U.S. military officials also cite an attack in September 2009 by helicopter-borne Special Operations Forces on a car in which one of east Africa's most wanted al Qaeda militants, Kenyan-born Saleh Ali Saleh Nabhan, was a passenger.
"We may have been able to capture the guy but the decision was made to kill him," a U.S. defense official said of the Somali operation. A factor in the decision, the official said, was uncertainty about "what would we do with him" if he was captured alive.
In many instances, operations never get off the ground because of the risks.
A former U.S. intelligence official said there were discussions late in the Bush administration about the possibility of using armed drones to help Mexican fight narco-traffickers. But the idea of "shooting missiles on the outskirts of Mexico City" ran into opposition, he said.
The Pentagon also considered taking military action in Somalia as intelligence poured in early last year about pirates establishing large camps from which they could launch attacks on commercial ships, counterterrorism and defense officials told Reuters.
The Navy had gone so far as to draw up plans for "lethal strikes" on the camps but the idea was nixed in part because of concerns about civilian casualties and what the U.S. military would do with those who are injured or captured given the country's lawless state. Some of the beachfront camps were set up in densely populated areas.
"The rhetorical question was: Should we go after the base camps," one official said. "We didn't go to their camps because of concerns about civilian casualties and about there not being a government there to turn them over to or to deal with the aftermath."
NATO's top commander, U.S. Admiral James Stavridis, told Reuters there were "active discussions" now about "taking actions ashore," from promoting development to discourage pirating to "burning skiffs, taking out camps." He said drones were "part of our operational footprint wherever we go."
PAKISTAN'S DEEPENING ROLE
An American diplomat tells a story about a meeting he had with Pakistani parliamentarians that offers a window into the tough position that nation is in when it comes to the drone attacks.
The message from each lawmaker seemed straightforward: CIA drone strikes against militants in the tribal areas bordering Afghanistan cause terrible damage and must stop.
Then, in the middle of the session, according to an account provided to Reuters, one of the parliamentarians slipped the American guest, who specializes in the region, a handwritten note: "The people in the tribal areas support the drones. They cause very little collateral damage. But we cannot say so publicly for reasons you understand."
U.S. officials say they go along with this "game" understanding that public acknowledgment of any Pakistani role in the U.S. targeted killings could have major implications for the government in Islamabad, already struggling in the face of militant accusations it is an American puppet.
A former U.S. intelligence official said the CIA was conducting the drone strikes instead of the U.S. military because the covert nature of the program gives Islamabad the "fig leaf of deniability."
"They can't stand up to their own people and say they're in league with the U.S.," the official said.
Anecdotal evidence cited by U.S. officials suggests that opposition to the drone strikes is stronger in major population centers, where the Taliban have less of a presence, than in the tribal areas, where the Taliban hold sway and the missiles rain down.
Significantly, U.S. and Pakistani officials say, there have been no major public protests against them, not even among the tribes being targeted.
Most of these attacks have targeted militant hideouts in remote mountainous areas, where there are few if any civilians. A tribal elder from North Waziristan, who declined to be identified, told Reuters: "People have chosen silence. They want to get rid of the Taliban and if the (Pakistani) army cannot do it now, then it (drone attacks) is fine with them."
"As long as things are moving forward, people's minds are changing. There is no anger against the strikes as long as civilians are safe. There have been civilian deaths but not in big numbers," the elder told Reuters.
Another tribesman, who did not want to be named for safety reasons, said: "We prefer drone strikes than army operations because in such operations, we also suffer. But drones hit militants and it is good for us."
Brigadier Asad Munir, a retired ISI officer, said the drone attacks have become "routine" in the tribal areas. "If they find 10 targets a day, they will do it. It will not spark any fresh anger," Munir said. "People have gotten used to it."
BEHIND THE FACADE
The truth is the CIA would not be able to find the militants in many cases without the help of Pakistan's spies and informants, officials say.
"You need guys on the ground to tell you who they (the targets) are and that isn't coming from some white guy running around the FATA. That's coming from the Pakistanis," a U.S. official said, referring to the semi-autonomous Federally Administered Tribal Areas along the Afghan border.
A Pakistan security expert, Ikram Sehgal, agreed. He said the intelligence underpinning the drone strikes has improved precisely because of increased Pakistani cooperation.
"The drone attacks after May last year have been very targeted and they have done a lot of good in terms of taking out the bad guys. And I think that has been possible because of the fact of Pakistan Army officers being in American camps in Afghanistan giving that actionable intelligence which is required," he said.
As the raw intelligence from the drones pours in, Pakistani intelligence liaisons work directly with CIA and military teams in Pakistan and Afghanistan to avoid miscommunication with agents and informants in the field. "We have Pakistanis around to help with coordination," a U.S. military official said.
But tension remains beneath the surface. While their leaders cooperate, many in the Pakistani military deeply resent the drone strikes, complicating efforts to bring Pakistan wholeheartedly on board in the battle against Islamist militants.
"This is a proud military and many hate the drone program because it is a constant reminder that they're not in control," a former U.S. intelligence official said.
CAN DRONES WIN THE WAR?
U.S. intelligence officials proudly tout the drone campaign as the most precise and possibly humane targeted killing program in the "history of warfare."
The target selection process is a secret but, according to the former intelligence official, individuals who are nominated to be "high-value targets" must be vetted by CIA lawyers to determine if they pose "a continuing and imminent threat."
The agency often uses specially designed missiles that have a small blast field with minimal shrapnel to limit "collateral damage", as unwanted casualties are known in military circles. Targets are often killed by the concussion created by the explosion.
Recent advances in drone technology also help to reduce civilian casualties. A U.S. official said: "Weapons can be steered away at the last moment if there's any possibility whatsoever that a non-combatant may be at risk. That speaks to the extreme precision of this system."
An official who has watched several drone strikes recalled the precision with which a CIA operator focused one of the drone's cameras on its target, identifying the wanted man by his missing left arm. A lawyer is always present, he said.
A senior U.S. government official said the strikes themselves may be more precise than ever, but target selection was only as good as the underlying intelligence.
While improved, U.S. officials acknowledge their limited ability to get first-hand intelligence. They rely heavily on satellite and drone imagery, and cell phone intercepts.
Even the Pakistanis have had difficulties in the past ensuring a reliable supply of intelligence in a region where people are often executed as spies.
One intelligence official estimated that as many as 70 Pakistani agents had been killed in the tribal areas and, at one point, areas around Miranshah in North Waziristan, the main Taliban and al Qaeda hub in the area, had become a black hole in terms of intelligence collection.
For some, however, it's not the technology or intelligence as much as the strategy that is flawed.
Addicott, the former legal adviser to Army Special Operations Forces, asks: "Are we creating more enemies than we're killing or capturing by our activities? Unfortunately, I think the answer is yes. These families have 10 sons each. You kill one son and you create 9 more enemies. You're not winning over the population."
"Drones don't impress them," Addicott added. "In the mind of the radicals we're cowards, we won't fight face-to-face. This is what they teach in the madrassas."
He is referring to the pro-Taliban religious schools which help produce many of the movement's anti-American foot-soldiers.
According to Sehgal, who is chairman of Pathfinder G4S, Pakistan's largest private security firm, these madrassas turn out between 7,000 and 15,000 "hard-core" students each year, eclipsing the number being killed by CIA drones and U.S. forces in Afghanistan.
Within the intelligence community, the verdict is still out on whether the CIA's targeted killing of Baitullah Mehsud degraded the Pakistani Taliban's capabilities -- one of the main objectives in any targeted killing.
Since his death last August, there have been fewer attacks against civilians in Pakistan -- 1,019 between August 6, 2009 and April 30, 2010, compared to 1,875 attacks between October 1, 2008 and August 5, 2009, according to a review of the U.S. National Counterterrorism Center's database.
But a U.S. counterterrorism official familiar with the data said the change was likely the result of Pakistani military offensives against militants in the tribal areas, rather than Mehsud's death, noting a downward trend in attacks prior to the August drone strike that killed him.
Baitullah's successor, Hakimullah Mehsud, may be even more ruthless.
"Although the number of attacks is down compared to before his death, the lethality is higher resulting in more deaths than normal for that level of attacks. That might indicate the militants are trying to maximize causalities or have changed tactics," the counterterrorism official said.
What is clear is that the issue of whether this military strategy is succeeding or not is not receiving very much attention in policy circles in Washington.
John Rizzo, who served as the CIA's top lawyer during the Bush administration, said he found it odd that while Bush-era interrogation methods like waterboarding came under sharp scrutiny, "all the while, of course, there were lethal operations going on, and think about it, there was never, as far as I could discern, ever, any debate, discussion, questioning ... the United States targeting and killing terrorists."
American University's Anderson said that could change if human rights group seize on the issue. "It could be the whole interrogation and detention thing all over again," he said.
Because of the sensitivities involved, the president himself has not brought up the drone controversy in public, with the exception of a joke at a black-tie dinner on May 1 attended by Washington journalists, politicians and celebrities.
Calling his two young daughters Sasha and Malia "huge fans" of the Jonas Brothers band, Obama cautioned the young pop stars: "Boys, don't get any ideas. I have two words for you -- Predator drones," the president said to laughter.
"You will never see it coming."
(Additional reporting by Zeeshan Haider and Kamran Haider in
Islamabad, Myra MacDonald in London and Phil Stewart and Caren Bohan in
Washington; editing by Jim Impoco and Claudia Parsons)