The world has entered an era of drone wars. In four major interstate wars in the last five years—those in Libya, Nagorno-Karabakh, Syria, and Ukraine—armed drones played a dominant, perhaps decisive, role. And yet the debates about drones still center on their use against nonstate actors, such as the Taliban, or speculation about their potential role in wars between the United States and near competitors, such as China. Those discussions have led many scholars to conclude that drones are so complicated and vulnerable as to be of limited use or relevance to wars between states. Some observers argue that drones may even promote international stability: countries may be less likely to escalate a conflict if a drone, rather than an aircraft with a human pilot, is shot down.

But mounting evidence points to a more disturbing trend. Cheap, survivable drones, combined with armor and artillery, offer the militaries that field them real advantages. The four recent conflicts in which drones have appeared show that even modest vehicles can help win military victories and reshape geopolitics. And as drones become part of the arsenals of more countries—surging from eight in 2015 to 20 today—new actors are poised to seize the opportunity they offer to grab territory or ignite previously frozen conflicts. Governments and analysts need to rethink the role these weapons may play in actually increasing the risk of interstate violence.

A Disposable Fleet

Scholars have long believed that offensive weapons are destabilizing, because they lower the costs of conquest while raising security fears among their potential targets. Armed drones take this idea even further. Unmanned vehicles are significantly less expensive than piloted aircraft, and militaries can send them on risky missions without fear of losing personnel. Moreover, because drones are cheap, countries can acquire them in numbers large enough to quickly swarm an adversary’s defenses. Militaries have already used dozens of drones in recent wars, and in future conflicts they are likely to deploy thousands, if not tens of thousands, to destroy or degrade opposing forces before they can mount a response.

Cheap, armed drones thus trade disposability for survivability. A military can afford to lose large numbers of them, so long as enough remain to destroy designated targets. Even if each drone is individually vulnerable, deploying them en masse provides safety in numbers. The cumulative effect can overwhelm even the strongest defenses.

Observers got a sneak peek of this tactic in Nagorno-Karabakh, where Azerbaijan recently used 1940s-era An-2 biplanes that were jury-rigged to operate remotely. The aircraft baited Armenian radar operators into turning their systems on, revealing their locations so that Azerbaijani pilots could destroy them from a distance with Israeli-made Harop drones. While Azerbaijan ultimately lost 11 An-2s, the strategy helped punch holes in Armenia’s aerial defenses.

Governments need to rethink the role that drones play in increasing the risk of interstate violence.

Early evidence from recent conflicts further suggests that basic armed drones might actually be more durable than initially assumed. Sophisticated Russian air defense systems, such as the S-300 and short-range Pantsir, proved surprisingly vulnerable in Libya, Nagorno-Karabakh, and Syria. In each case, armed drones were able to escape detection and exploit coverage gaps in older systems built with larger piloted aircraft in mind. Unmanned vehicles destroyed several Russian Pantsirs in Libya and Syria and feasted on older air defense systems in Armenia.

For states that seek to break long-standing geopolitical deadlocks, the rise of relatively cheap, disposable, armed drones offers a tempting opportunity. Such vehicles can help states grab territory quickly, rapidly overwhelm their opponents, and threaten greater punishment in the future.

Game Changer

Drones have become all the more alluring as they have succeeded in turning the tide on actual battlefields. Turkey has used drones to particular effect. A Syrian airstrike killed 36 Turkish soldiers operating near Syria’s northern Idlib Province last February, and Ankara retaliated by using TB2 drones to destroy dozens of tanks, air defenses, and armored vehicles, killing hundreds, possibly thousands, of Syrian soldiers. On behalf of a chastened Syria, Russia requested a cease-fire. Turkish TB2s were also decisive in breaking a military stalemate in Libya during Operation Peace Storm: the combined weight of TB2 drones and ground forces drove Libyan National Army forces from Tripoli and their stronghold in Tarhouna.

Armed drones did not work alone, however. Unmanned systems are most effective as force multipliers, working in conjunction with such traditional hardware as artillery and long-range missiles or in support of mobile ground units. Azerbaijan, for example, used its drones to identify Armenian defensive positions and then guide indirect fire from artillery and rocket launchers. Drones can now substitute for traditional airpower and make these and other platforms more lethal. Their very presence on the battlefield changes their targets’ calculations at nearly every level of decision-making.

Countries that invest in armed drones face a powerful temptation to restart territorial conflicts

Militaries that know their adversaries are using drones are forced to change their behavior to counter an aerial threat. Normally mobile armored vehicles in both Libya and Nagorno-Karabakh hunkered down in fortified positions to lower their visibility from above. Unable to leave their defensive positions, these forces couldn’t coordinate offensives and ended up ceding momentum to their enemies. The Libyan National Army and Armenian forces could have protected their vulnerable formations by better integrating them with air defenses, but only at the cost of chaining them to the range and availability of those systems. Moreover, the threat of armed drones appearing suddenly in supposedly safe rear areas complicates the movement of reserves and supplies.

In short, drones are revising the modern war playbook in real time. Even today’s relatively simple vehicles are lethal and durable enough to tip the balance in regional conflicts. With surprisingly limited capabilities, drones can help states exploit new opportunities on the battlefield.  

Offense Takes the Lead

Armed drones are not unbeatable. Indeed, they are limited, even crude, devices, vulnerable to electronic jamming, tethered to air bases, and often grounded by poor weather. Capable of carrying only modest payloads, drones like the TB2 have short ranges of only 93 miles from ground control or repeater stations. For all its success, Azerbaijan lost several TB2s to Armenian ground fire, as did both Turkey and the United Arab Emirates in Libya.

Analysts should resist the temptation to exaggerate the effects of armed drones: these vehicles do not cause conflict so much as they enable it. But neither should observers overlook drones’ destabilizing potential. Simple unmanned aircraft have helped states break long-standing stalemates. Tomorrow’s armed drones, propelled by rapid innovations in the commercial sector, will likely prove to be even more effective. Turkey is already working to extend the range of the TB2s used over Nagorno-Karabakh barely four weeks ago. And as unit costs fall, mass-produced drones will soon be able to swarm enemy defenses. In time, drones with individualized capabilities might combine to form hunter-killer teams to exploit an enemy’s battlefield vulnerabilities. With such affordable technology at hand, leaders may be hard-pressed to resist the temptation to restart frozen wars or even instigate new ones, especially if they believe that their advantages are temporary.

Already, some countries are investing in systems to counter drones, but these technologies are in their infancy. The defense is playing catch up while the offense marches downfield. The gaps in short-range, low-level air defenses will be difficult to plug, at least in the near term. And offensive technology is simply cheaper: a Russian S-400 Triumpf missile system costs $300 million and a Pantsir, about $14 million. By contrast, a TB2 costs only $5 million, and its MAM-L missile, used to deadly effect in Nagorno-Karabakh, comes at only $100,000 a pop. Countries that rely on expensive legacy systems for defense might find themselves unable to afford to protect their armies or replace their wartime losses. Until defenses shift to drone-based countermeasures, these costly systems will likely remain vulnerable.

Those countries that invest in armed drones will face a powerful temptation to restart simmering territorial conflicts or seek new advantages in those that have deadlocked. Chillingly, of the next ten countries predicted to acquire armed drones, nine are trapped in long-running territorial disputes or fighting internal wars. The international system may soon face a new round of conflicts propelled by the proliferation of armed drones.

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