For streamlined, unmanned aircraft, drones carry a lot of baggage these days, along with their Hellfire missiles. Some people find the very notion of killer robots deeply disturbing. Their lethal operations inside sovereign countries that are not at war with the United States raise contentious legal questions. They have become a radicalizing force in some Muslim countries. And proliferation will inevitably put them in the hands of odious regimes.
But most critics of the Obama administration’s aggressive use of drones for targeted killing have focused on evidence that they are unintentionally killing innocent civilians. From the desolate tribal regions of Pakistan have come heartbreaking tales of families wiped out by mistake and of children as collateral damage in the campaign against Al Qaeda. And there are serious questions about whether American officials have understated civilian deaths.
So it may be a surprise to find that some moral philosophers, political scientists and weapons specialists believe armed, unmanned aircraft offer marked moral advantages over almost any other tool of warfare.
“I had ethical doubts and concerns when I started looking into this,” said Bradley J. Strawser, a former Air Force officer and an assistant professor of philosophy at the Naval Postgraduate School. But after a concentrated study of remotely piloted vehicles, he said, he concluded that using them to go after terrorists not only was ethically permissible but also might be ethically obligatory, because of their advantages in identifying targets and striking with precision.
“You have to start by asking, as for any military action, is the cause just?” Mr. Strawser said. But for extremists who are indeed plotting violence against innocents, he said, “all the evidence we have so far suggests that drones do better at both identifying the terrorist and avoiding collateral damage than anything else we have.”
Since drone operators can view a target for hours or days in advance of a strike, they can identify terrorists more accurately than ground troops or conventional pilots. They are able to time a strike when innocents are not nearby and can even divert a missile after firing if, say, a child wanders into range.
Clearly, those advantages have not always been used competently or humanely; like any other weapon, armed drones can be used recklessly or on the basis of flawed intelligence. If an operator targets the wrong house, innocents will die.
Moreover, any analysis of actual results from the Central Intelligence Agency’s strikes in Pakistan, which has become the world’s unwilling test ground for the new weapon, is hampered by secrecy and wildly varying casualty reports. But one rough comparison has found that even if the highest estimates of collateral deaths are accurate, the drones kill fewer civilians than other modes of warfare.
Avery Plaw, a political scientist at the University of Massachusetts, put the C.I.A. drone record in Pakistan up against the ratio of combatant deaths to civilian deaths in other settings. Mr. Plaw considered four studies of drone deaths in Pakistan that estimated the proportion of civilian victims at 4 percent, 6 percent, 17 percent and 20 percent respectively.
But even the high-end count of 20 percent was considerably lower than the rate in other settings, he found. When the Pakistani Army went after militants in the tribal area on the ground, civilians were 46 percent of those killed. In Israel’s targeted killings of militants from Hamas and other groups, using a range of weapons from bombs to missile strikes, the collateral death rate was 41 percent, according to an Israeli human rights group.
In conventional military conflicts over the last two decades, he found that estimates of civilian deaths ranged from about 33 percent to more than 80 percent of all deaths.