WASHINGTON // With unmanned aerial drones hitting their first targets around Misurata last week, the US has stepped back into the breach in Nato's month-long military campaign over Libya.
But the use of Predator drones, while a tactic US military planners seem to increasingly rely on, will not significantly alter the military balance of power in Libya, say analysts, and could instead prove highly controversial, as it has in Pakistan.
The American use of drones is hugely unpopular in Pakistan where they are seen as a tool for assassination from on high, the cause of many civilian casualties and a violation of Pakistan's sovereignty.
On April 22, a drone strike in North Waziristan, one of Pakistan's north-west frontier regions, killed 25 people. Of those, at least eight were civilians, five women and three children, according to news reports.
Such strikes have prompted nationwide demonstrations in Pakistan and at one such protest in Peshawar a week ago , the cricketer-turned-politician, Imran Khan, urged the Pakistani government to speak out against the US drone operations over the country.
The official position of the Pakistani government is that the use of US drones over Pakistan constitutes a violation of the country's sovereignty. But classified US diplomatic cables revealed by WikiLeaks last year show that there has been close co-ordination between the countries over strikes, and, in private conversations with US diplomats, at least some Pakistani officials appear not in the least unhappy about them.
Moreover, say analysts, the intelligence gathering needed to identify targets for the drone attacks - which statistics suggest are getting more accurate in avoiding civilian casualties - would be impossible without at least some co-operation with Inter-Services Intelligence, ISI, Pakistan's intelligence agency.
"Capability here is a function of human intelligence, and human intelligence is not coming from the American intelligence community," said Kamran Bokhari, the director of Middle East and South Asia analysis at STRATFOR, a Texas-based global intelligence company. "It is coming from the Pakistani intelligence community."
Such co-operation is "not very robust", Mr Bokhari acknowledged, with the ISI conflicted over the US drone operations. But it exists and is necessary for identifying targets and keeping down civilian casualties. With no similar intelligence capabilities in Libya, it is not clear how drones could be deployed to significant effect.
"The main thrust of intelligence in Libya is from the rebels, and the biggest problem with the rebels is they're not in the area where [Libyan Leader Moammar] Qaddafi is," said Mr Bokhari. "So you really have a need for intelligence."
So far, little is clear about the drone mission in Libya. The targets that were hit last week were military, of the kind that could be identified from the air. Their deployment, said Mr Bokhari, is likely a response to the conflicting pressures on the US administration, for greater involvement from America's European allies, and for as little involvement as possible from the US military, already stretched in Iraq and Afghanistan and reluctant to get deeply involved in yet another conflict.
But in Pakistan the use of drones has expanded significantly over the years. The first reported use was in 2004. In 2008, under the Bush administration, the aerial campaign was significantly stepped up, and it has further expanded under the Obama administration.
The US does not officially comment on drone strikes in Pakistan, but US officials are understood to be satisfied that the tactic is having an effect. Indeed, the drone strikes seem to remain, as Leon Panetta, the director of the CIA and soon-to-be defence secretary, commented in 2009, "the only game in town", at least in Pakistan.
This reliance on drone strikes is borne out by numbers compiled - from major news agencies, including Pakistani media outlets - by Katherine Tiedemann and Peter Bergen of the New America Foundation, a Washington-based think-tank. In 2009, the number of killings ranged from a low estimate of 368 to a high of 724. In 2010, the number of strikes more than doubled, killing between 607 and 993.
With the numbers compiled so far for this year - a low estimate of 122 deaths from drone strikes to a high of 177 - the programme seems "pretty much on pace" for 2011, said Ms Tiedemann.
Ms Tiedemann noted that reports also reflect a falling civilian fatality rate, "probably", she said, a result of "more intelligence sharing" between Pakistan and the US. Keeping the civilian fatality rate low in Pakistan will be crucial to heading off domestic anger at the tactic as well as criticism by human rights groups, including the American Civil Liberties Union, that the tactic is illegal since it constitutes "targeted killings" without legal oversight outside a war zone.
In Libya, where international forces are UN-mandated, the same criticism may not apply, but the absence of intelligence on the ground carries with it the risk that should the drones become a feature of Nato's air campaign, civilian casualties could increase. That in turn could undermine international support for the international intervention, not least from Arab countries.
Much depends on how the drones will ultimately be used.
"These aircraft are designed to take out enemy leadership," Mr Bokhari said. "But it's not really clear, even as drones are being inserted into this theatre, if regime change is the goal."
And without a clear mission or better intelligence from the ground, Mr Bokhari said, it is unlikely that the insertion of drones over Libya will have any dramatic effect on the military situation there.