Drones are everywhere. They are blasting suspected al-Qaida militants in Pakistan, Yemen, and Somalia. They are menacing China. They are being shot down in Israel. They are hovering outside of homes in America and spying on their residents. And they are forcing us to rethink some basic legal principles—for good reason, because drones are making the old ones obsolete.
Drones have existed for decades, but in recent years they have become ubiquitous. Some people celebrate drones as an effective and humane weapon because they can be used with precision to slay enemies and spare civilians, and argue that they pose no special risks that cannot be handled by existing law. Indeed, drones, far more than any other weapon, enable governments to comply with international humanitarian law by avoiding civilian casualties when attacking enemies. Drone defenders also mocked Rand Paul for demanding that the Obama administration declare whether it believed that it could kill people with drones on American territory. Existing law permits the police to shoot criminals who pose an imminent threat to others; if police can gun down hostage takers and rampaging shooters, why can’t they drone them down too?
While there is much to be said in favor of these arguments, drone technology poses a paradox that its defenders have not confronted. Because drones are cheap, effective, riskless for their operators, and adept at minimizing civilian casualties, governments may be tempted to use them too frequently.
Indeed, a panic has already arisen that the government will use drones to place the public under surveillance. Many municipalities have passed laws prohibiting such spying even though it has not yet taken place. Why can’t we just assume that existing privacy laws and constitutional rights are sufficient to prevent abuses?
To see why, consider U.S. v. Jones, a 2012 case in which the Supreme Court held that the police must get a search warrant before attaching a GPS tracking device to a car, because the physical attachment of the device trespassed on property rights. Justice Samuel Alito argued that this protection was insufficient, because the government could still spy on people from the air. While piloted aircraft are too expensive to use routinely, drones are not, or will not be. One might argue that if the police can observe and follow you in public without obtaining a search warrant, they should be able to do the same thing with drones. But when the cost of surveillance declines, more surveillance takes place. If police face manpower limits, then they will spy only when strong suspicions justify the intrusion on targets’ privacy. If police can launch limitless drones, then we may fear that police will be tempted to shadow ordinary people without good reason.
Similarly, we may be comfortable with giving the president authority to use military force on his own when he must put soldiers into harm’s way, knowing that he will not risk lives lightly. Presidents have learned through hard experience that the public will not tolerate even a handful of casualties if it does not believe that the mission is justified. But when drones eliminate the risk of casualties, the president is more likely to launch wars too often.
The same problem arises internationally. The international laws that predate drones assume that military intervention across borders risks significant casualties. Since that check normally kept the peace, international law could give a lot of leeway for using military force to chase down terrorists. But if the risk of casualties disappears, then nations might too eagerly attack, resulting in blowback and retaliation. Ironically, the reduced threat to civilians in tactical operations could wind up destabilizing relationships between countries, including even major powers like the United States and China, making the long-term threat to human life much greater.
These three scenarios illustrate the same lesson: that law and technology work in tandem. When technological barriers limit the risk of government abuse, legal restrictions on governmental action can be looser. When those technological barriers fall, legal restrictions may need to be tightened.
These anxieties generate some standard meta-arguments that are now little more than incantations—that the president should consult with Congress more, or should use clearer standards when targeting enemies, or should be less secretive. The generic criticisms overlook basic practical hurdles. Secrecy is necessary to gather intelligence. Standards for targeting enemies will always be fuzzy because it’s difficult to anticipate the shape of future threats. (The much-criticized DOJ rules for drones are hardly less clear than the rules governing ordinary police work.) And both of these factors mean that Congress can never play more than a formulaic role.
Bans on the use of drones for domestic surveillance are premature. But U.S. courts should ready themselves to update surveillance rules to take into account drones, as well as technology like the GPS tracking devices discussed in U.S. v. Jones. Courts need to address how these technologies can be abused and whether police seem to be abusing them, and they will need to use more flexible rules than the trespass standard the Supreme Court has adopted so far. A rule against trespassing without a warrant won’t stop police drones mounted with video cameras and image-identifying software from lingering outside every home as they search for suspected crooks.
When it comes to presidential power, only time will tell whether the risks of blowback exceed the value of drones. Many critics seem confident that President Obama’s drone war has undermined American security, but we do not know what would have happened if he had shown more restraint. Nonetheless, it is quite a paradox that we trust the president with nuclear weapons because we know that he cannot use them, while we may not trust the president with drones because we know that he can.
Internationally, nations might benefit from an arms control agreement governing drones, but it is hard to imagine any such agreement in the near future, given uncertainties about how drone technologies will develop, the difficulty of monitoring drones, and the asymmetries that mean the best-equipped states will resist any constraints. But a starting point is to recognize that the laws of war currently favor drones because they limit civilian casualties, while disfavoring conventional weapons—a surefire recipe for a destabilizing arms race.
It would be nice to think that future wars will be fought by robots, with no risk to civilians or even soldiers—just as in ancient times a duel between heroes could settle a dispute between armies without a battle. But the gods liked to play havoc with duels, and drone warfare is likely to be similarly unpredictable. The long-predicted science-fiction world of robotic killing machines has finally arrived. The law now has to catch up.