The best estimate of the number of people killed in US drone strikes over the past eight years comes from the Bureau of Investigative Journalism: between 2532 and 3251 dead in Pakistan, Yemen and Somalia. Of those, between 475 and 879 deaths were civilian non-combatants who just happened to be nearby when the Hellfire hit - often because they were trying to rescue survivors from an earlier strike.
The Stanford/New York University study, entitled Living Under Drones, describes the Bureau of Investigative Journalism's database as "far more reliable than other aggregating sources", based on a far wider range of sources than other comparable studies. And of course there are no official numbers. The US Government doesn't even try to count the casualties.
Washington doesn't formally admit that the Central Intelligence Agency is running a remote-control assassination programme, because it is legally a dubious area. At the same time, it strives to reassure Americans that there is almost no "collateral damage": that practically all the victims are "bad guys". Including the 175 children who, going be the bureau's numbers, have been killed in the strikes.
Let's be honest: children always get killed in air strikes. When you explode 10kg of high explosives on a single target (the standard Hellfire load), there can be nothing surgical about it. The really questionable aspects of the CIA's drone programme lie elsewhere.
First, is it legal to make air attacks in a country with which you are not at war? Second, can you distinguish sufficiently between "militants" and civilians living in the same area? And, above all, why make double-tap attacks?
The legal question is particularly problematic in Pakistan, where the Government has not authorised the US to carry out attacks. Islamabad tacitly accepts them, but sometimes public opinion forces it to respond vigorously, as when an American missile killed 24 Pakistani soldiers last year. That blunder also highlights the difficulty of distinguishing between "militants" and civilians through the lens of a remote-controlled camera.
It's the double-tap attacks that are truly shameful. Do the controllers really think that the people rushing to rescue the survivors of a first strike are all "militants" too? Or are they just trying to deter people from helping those who were wounded in the first strike? That is certainly the effect of the policy: villagers now often leave the injured survivors of an attack in agony for hours before going to help them, for fear of becoming victims too.
It is pointless to tell the military and their masters this tactic is counter-productive, generating more new "militants" than it kills. The bureaucratic machine doesn't respond to such subtle arguments. Probably, there's no point in talking about the moral problem of killing innocents either. But the fact that 50 countries now have drones should inspire a little reflection about this unwritten change in the rules of engagement.
The latest proud possessor of these weapons is Iran, which has just unveiled a new drone with a range of 2000km, capable of flying over most of the Middle East. If it is really copied from the US drone that Iran captured last year, then it has major air-to-ground capabilities. So what if it starts using those capabilities over, say, Syria, against the rebels that the Syrian Government calls "terrorists"?
The US could not really complain (though no doubt it would). What's sauce for the goose is sauce for the gander.
Gwynne Dyer is an independent journalist with articles published in 45 countries.