Of the 60 people who have died in 14 reported drone attacks in Pakistan tribal areas since September, the names of all but one of the victims, an alleged leader of the Haqqani terror network named Janbaz Zadran, remain classified.

Since 9/11, the United States has dramatically expanded its covert drone program, killing between several hundred to more than 2,000 people, mostly in Afghanistan, Pakistan, Somalia, and Yemen, according to human rights groups. Carried out it in near total secrecy (even the existence of the drone program is classified), it's impossible for outsiders to assess whether U.S. kill operations meet the standards of international law.

The drone program has proven highly controversial in Yemen -- where a U.S. strike, prompted by bad intelligence, in May, resulted in the killing of a Yemeni official -- and in Pakistan, where it has strained U.S. relations with a key ally in the war on terror. Last month, the Central Intelligence Agency temporarily suspended drone operations in Pakistan in an effort to repair the two countries' relationship. But the U.N. leadership has shown little interest in registering concern about a practice considered highly controversial -- even before the United States launched its war on terrorism after 9/11. While some of Washington allies' are reportedly troubled by the scope of the U.S. killing campaign they have registered little public concern about it at the United Nations, leaving Iran as a relatively lone voice of protest against the program following their capture of an American surveillance drone in December.

Last month, Turtle Bay asked U.N. Secretary General Ban Ki-moon at his year-end press conference about his views on the use of drones, and whether he worries about countries like Iran or Russia taking up the practice. "I don't have much to say about all this, what kind of means the member states use," Ban answered. "This is something which national governments, military authorities, they may decide."

Ban said that while he hoped these nations act within the bounds of "international regulations and understandings" he realizes that "with the rapid development of technology, many countries develop their own military means of getting, collecting information. Other than that, I do not have comments on this matter."

Ban's reluctance to address the drone policy stands in contrast to his predecessor Kofi Annan's criticism of other controversial aspects of the U.S. led war on terror, particularly its detention and rendition policies.

Ban's human rights chief, Navi Pillay, has also kept relatively silent about the U.S. drone program, though she has expressed concern about President Barack Obama's decision to order a targeted killing of Osama Bin Laden..

Pillay's aides said that international law does allow for the use of targeted killings in the course of an armed conflict. "The issue of drones is a very complex one, and depends on the circumstances in which they are used," Pillay's spokesman, Rupert Colville, told Turtle Bay in an email. "When used in the course of an armed conflict the use of armed drones must respect all norms of International Humanitarian Law -- in other words the same norms applicable to any other weapon.... When used outside the context of an armed conflict, a number of rules and principles of general international human rights law would become relevant, and each situation would have to be assessed on the basis of its own particular set of facts -- which makes it a bit difficult to generalize."

The Obama administration sees the drones as an important asset in the U.S. effort to confront al Qaeda at a time when U.S. forces have withdrawn from Iraq and are prepared to scale back in Afghanistan. They say that they inflict far fewer casualties on civilians than cruder weapons.

"Al Qaeda seeks to bleed us financially by drawing us into long, costly wars that also inflame anti-American sentiment," John Brennan, the White House top counter-terrorism official, said in a June speech at the Johns Hopkins University's School of Advanced International Studies (SAIS). "Under President Obama, we are working to end the wars in Iraq and Afghanistan responsibly, even as we keep unrelenting pressure on al-Qaeda. Going forward, we will be mindful that if our nation is threatened, our best offense won't always be deploying large armies abroad but delivering targeted, surgical pressure to the groups that threaten us."

In a separate speech in September at Harvard Law School, Brennan suggested that there needs to be a more "flexible" legal basis for targeted killings, citing the global and technological sophistication of terror groups like al Qaeda. "The traditional conception of what constitutes an ‘imminent' attack should be broadened in light of the modern-day capabilities, techniques, and technological innovations of terrorist organizations," he said.

The only U.N. official to address drones in recent years is Philip Alston, a New York University law professor and a former U.N. special rapporteur for extrajudicial, summary or arbitrary executions, who filed a report criticizing the lack of transparency surrounding the use of drones before the U.N. Human Rights Council. But Alston, who stepped down from his U.N. position in July 2010, served the U.N. as an independent expert, and his findings and recommendations have no official bearing on the institution.

For Alston, the debate over the legality of the drone attacks misses the point. "There is no meaningful domestic accountability for a burgeoning program of international killing," Alston argued in a recent paper. "The result is the steady undermining of the international rule of law, and the setting of legal precedents which will inevitably come back to haunt the United States before long when invoked by other states with highly problematic agendas."

On Dec. 16, Human Rights Watch (HRW) weighed in, writing Obama a letter urging him to clarify the legal rationale for targeted killings, and transfer command of the aerial drone strikes from the CIA to the U.S. military. In the past year, "the use by the United States of Unmanned Combat Aircraft Systems (drones) to conduct targeted killings has expanded rapidly in Pakistan and other countries. Yet, your administration has taken few steps to provide greater transparency and accountability in conducting targeted killings, intensifying concerns both in the US and abroad about the lawfulness of these attacks."

The legal and policy director of HRW said in a Dec. 19 statement that "CIA drone strikes have become an almost daily occurrence around the world, but little is known about who is killed and under what circumstances." The group continued: the United States is setting deeply troubling precedents which will redound to its detriment when invoked by other states seeking justifications for their own efforts to flout international legal prohibitions on arbitrary executions."

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