Why Sticks and Stones Will Beat Our Drones

The persistent dangers of low-tech warfare.

"I know not with what weapons World War III will be fought," Albert Einstein warned President Truman, "but World War IV will be fought with sticks and stones."

It doesn't do to quarrel with Einstein, and he's no doubt right about World War IV. But implied in Einstein's famous adage is an assumption that right up until the moment we knock ourselves back into the Stone Age, the technologies of warfare will evolve in one direction only: They will become ever more advanced, complex, sophisticated, and lethal.

Today, much rhetoric about future wars makes this assumption. We assume that military technological innovation is a one-way ratchet. High tech measures taken by one side will be followed by high-tech countermeasures taken by the other, which will be met with still more advanced counter-countermeasures, and so on, ad infinitum -- or at least until some Einsteinian nuclear catastrophe ends the cycle, crashing us back to the age of sticks and stones.

But Einstein's cautionary words overlook one detail: For all our technological sophistication, warfare has never truly moved past sticks and stones -- and even today, their bone-breaking power remains surprisingly potent.

Technological Teleology

It's easy to forget the continued role of sticks and stones. When we think of the history of warfare, we think in terms of perpetually advancing technologies. Certainly, history offers plentiful examples of escalating technological "measure, countermeasure, counter-countermeasure" cycles: As swords and spears grew more lethal, armor became heavier. As armor became heavier, horses were needed to increase speed and maneuverability, and the invention of the stirrup further increased the lethal effectiveness of mounted cavalry. The development of the long-bow enabled distance warfare and the decimation of mounted troops armed with swords and spears, but then guns and artillery displaced longbows, automatic weapons displaced single-shot weapons, and so on through the atom bomb -- for which Einstein's work so ambivalently paved the way.

Or consider electronic warfare. During World War II, for instance, Allied forces developed active sonar to locate submerged German U-Boats, while ship-based high-frequency radio direction finders were produced to intercept radio transmissions sent by surfaced U-Boats. Germany then equipped U-Boats with radar detectors, which led the Allies to deploy newly developed centimetric radar, which German radar detectors could not detect. In the context of aerial warfare, the evolution of radar systems to detect incoming aircraft led to the use of chaff and the development of radar jammers, which in turn led to new counter-countermeasures intended to making jamming more difficult, such as frequency hopping and radiation homing.

In each of these cases, technological innovation in warfare sparked new technological innovations by adversaries, and today, as in World War II, we're often inclined to assume the inevitability of such technological escalation.

This is the assumption that underlies much current thinking about cyber-threats, as well as the Pentagon's Air-Sea Battle paradigm. In cyber, the development of Internet-based communications systems is countered by the development of new methods of detecting and disrupting Internet communication; cyberattacks lead to new cyber-defenses, which lead to new and more sophisticated cyberattacks. The Air-Sea Battle paradigm is similarly premised on the assumption that technology marches forward: U.S. air and naval dominance incentivizes near-peer competitors -- a.k.a. frenemies, a.k.a. China -- to develop anti-access and area denial technologies. And so, the logic goes, we need to invest in anti-anti-access technologies, and technologies to deny area denial.

This, of course, just happens to take money, and lots of it. It also just happens to involve significant investment in the Air Force and Navy, the two services pushed to the sidelines, relatively speaking, during a decade of slow, plodding land war in Iraq and Afghanistan. Fearing displacement themselves, the Army and Marines are pushing their own high-tech visions of their future. As Lloyd Freeman argued in these pages last week, the Marine Corps needs to transform itself, for "in future conflicts, [ground troops] will only play a secondary role. Land forces will no longer win wars. Computers, missiles, planes, and drones will." In the future, argues Freeman, the old "every Marine a rifleman" slogan will need to be replaced with a new concept: "every Marine a JTAC" (joint terminal air controller). "Marines will manage and become experts on dozens of different communications platforms," asserts Freeman. "Live video feeds will stream continuously."

Maybe so, maybe not.

Here's what we seem eager to forget: Military technological evolution can go in both directions. In biological evolution, there's no teleology: The simple doesn't inevitably become more complex, and while life forms change and evolve in response both to random mutation and environmental conditions, they don't inevitably "advance." In modern warfare, the same is true. High-tech measures aren't inevitably countered by more high-tech measures. Sometimes, the opposite is true: The most successful countermeasures are low-tech -- and historically, this has been demonstrated just as often as has the opposite.

We know this, of course. We just don't like it.

Sticks and Stones in Afghanistan

Consider, most recently, the U.S. experience in Afghanistan. The U.S. brought overwhelming technological superiority to the battlefield -- and with it, we also brought new blind spots. The Taliban, a low-budget but by no means low-innovation adversary, quickly developed low-tech responses to our high-tech blind spots.

Unable to prevail in direct combat with U.S. troops, for instance, the Taliban turned to improvised explosive devices made of readily available materials and detonated by cell phone. We countered by developing costly vehicle-based cell-phone jammers, designed to prevent the long-distance detonation of IEDs as our vehicles drove by them. These often had the unintended consequence of disrupting our own communications, and they also led the Taliban to shift to using IEDs with mechanical triggers. We responded by equipping our forces with ground-penetrating radar designed to detect the metallic signature of IED components. The Taliban countered by moving even further in the direction of sticks and stones, constructing pressure-plated IEDs out of foam rubber, plastic, and wood.

We've seen similar Taliban low-tech countermeasures in other areas. We have invested heavily in both encryption technologies and surveillance technologies designed to thwart adversaries' use of encryption, for instance, but since we took it for granted that potential adversaries would have made similar high-tech communications commitments, we allowed our ability to locate simple FM radios to degrade.

Most of the time, Taliban forces don't bother with encryption; they communicate openly over simple handheld walkie-talkies, using multiple mobile FM repeaters to retransmit these weak signals over longer distances. U.S. forces initially lacked the equipment needed to intercept these transmissions, and reportedly had to reply on purchasing cheap "commercially available radio scanners in the Kabul souk" to listen in. The equipment needed to intercept Taliban radio communications became standard, but it has proven far more difficult for us to locate the enemy themselves; we can locate the repeater towers, but not a Taliban soldier on his handheld radio.

Al Qaeda, too, is a learning organization. Threatened by U.S. drones, al Qaeda is reportedly turning to low-tech countermeasures, encouraging militants to use mud and grass mats to disguise vehicles from overhead surveillance. This tactic won't be successful for long, but it's a good bet that AQ will find new low-tech means to thwart U.S. drones in the coming years.

You get the picture. Sometimes, high-tech measures leads to higher-tech countermeasures -- but at other times, high-tech measures lead to lower-tech countermeasures. More ominously, a misplaced confidence in our technological superiority dangerously increases our vulnerability to low-tech countermeasures.

The Moral of the Story

Some will be tempted to dismiss this as an artifact of the ill-fated post-9/11 U.S. ground wars. Though 65,000 U.S. troops remain in Afghanistan, we've already begun to lose interest in that war and its lessons. We should know better.

In the 1970s, we convinced ourselves that there would be no more Vietnams, and turned our backs on whatever wisdom we had gained during that brutal, protracted conflict (wisdom about the nature of asymmetric and guerilla warfare, the strength of nationalism and the perils of occupation). Then, in Iraq and Afghanistan, we painfully relearned many of Vietnam's grim lessons -- just in time for the wars to wind down and the public to lose interest.

Now, many leaders in both the military and civilian world seem determined to repeat our post-Vietnam head-in-the-sand routine. We won't have any more Iraqs or Afghanistans, we tell ourselves -- we won't invade or occupy states or territories with vast ground forces, and we won't be engaged in messy COIN or stability operations, so we don't need to remember our mistakes -- we can just move on! The lessons of Afghanistan will have no applicability to future wars, for these future wars, if any, will be high-tech conflicts with sophisticated state or state-backed adversaries.

Maybe so, maybe not.

Here's the thing: Even if the cyberwarriors and the Air-Sea Battle proponents are right -- even if any future wars will be with sophisticated, high tech states -- it's a big mistake to imagine that sticks and stones will play no role in future conflicts.

After all, it took the Taliban remarkably little time to realize that high-tech U.S. capabilities could frequently be thwarted by lower-tech countermeasures. Why should we imagine that near-peer states such as China haven't taken notice?

Aref Karimi/AFP/Getty Images

National Security

Let Them Go

Why John Brennan should give a passport and $10K to every Gitmo prisoner.

Why not just let them go?

The fear that detainees at Guantánamo or Afghanistan might "return to the battlefield" if released remains an ongoing feature of debates about U.S. detention policy. The concern isn't entirely frivolous: Some former detainees have taken up arms against the United States after gaining their freedom. But here's my heretical thought of the week: So what? Or, more precisely: Isn't it time to recognize that the dangers associated with releasing detainees might be outweighed by the dangers associated with continuing to hold them?

Under the law of war, states can detain enemy combatants as prisoners of war for the duration of the conflict, in order to keep them off the battlefield. But historically, many states -- including the United States -- have engaged in routine prisoner exchanges during armed conflicts, freeing enemy prisoners in exchange for the return of our own prisoners. (During World War II, we even exchanged some POWs with the Nazis). The long-standing practice of prisoner exchanges implies something we often seem to forget these days: Sometimes, letting bad guys go is much more useful than hanging on to them.

We're reaching that point in the Afghanistan conflict. On Monday, U.S. military authorities formally transferred control of Afghanistan's Parwan detention facility to the government of Afghanistan. The transfer of the facility, which holds some 4,000 people detained by coalition forces during a decade of war, had been delayed and delayed again due to U.S. fears that Afghan authorities would simply release many of the detainees -- who would end up "returning to the battlefield." But as an unnamed U.S. official told the New York Times, there's "a shift that's going on in how the U.S. is looking at what's important.... We have to look at the larger picture: What's the U.S. strategic interest here?"

Right. What's better for the United States after a dozen years of war, and with plans for a large-scale troop withdrawal in 2014: holding on to every last Taliban detainee "just in case," or letting the Afghans figure out what to do with the detainees -- even if it means that some are released and rejoin the Taliban?

Whether the U.S. effort in Afghanistan succeeds or fails surely does not depend on whether a few thousand Taliban detainees return to being Taliban fighters. No one knows for sure how many fighters the Taliban has in the first place, but estimates range from 25,000 to 40,000. Arrayed against roughly 350,000 members of the Afghan National Security Forces (not to mention the remaining U.S. troops), it's hard to imagine that tossing a few thousand Taliban fighters back into the mix will be a decisive factor, even in the unlikely event that Afghan authorities engage in a wholesale prisoner release.

In part, this is because Taliban fighters appear to be a renewable resource: With or without detainees released from Parwan or other facilities, the Taliban seem quite effective in recruiting new young men to serve as cannon fodder. (Most will occupy only low-level roles, and most will not live long.) And the continued detention of thousands of Afghans by the United States plays a role in ensuring a steady stream of Taliban recruits.

That role is impossible to quantify, but difficult to doubt: Afghan President Hamid Karzai has frequently made clear how bitterly his government -- our putative partner against the Taliban -- resented U.S. control over Parwan. Perhaps more tellingly, ordinary Afghans express striking ambivalence about the presence of international forces: Two years running, for instance, three-quarters of Afghans surveyed by the Asia Foundation say they have "some" or "a lot" of fear about encountering international forces.

It's impossible to determine the degree to which fear and resentment of U.S. detention policies drives Taliban recruiting efforts; night raids, air strikes, frightening checkpoint encounters, and the U.S. role in enabling Karzai's corrupt government undoubtedly also play a role in inspiring armed resistance to what many Afghans view as foreign occupation. But it seems reasonable to assume that Afghan unhappiness with U.S. detention policy is part of that picture.

We thus have to weigh the potential costs associated with releasing Afghan prisoners -- some of whom will likely "return to the battlefield" -- against the potential costs of not releasing them. These costs include the distinct possibility that our continued detention of thousands of Afghans could inspire just as many new Taliban recruits.

This logic seems to have finally won out, as evidenced by this week's transfer of authority for the Parwan detention facility to the Afghans. But the fear of recidivism hasn't fully receded: According to the New York Times, the long impasse over Parwan was resolved only when U.S. officials received "private assurances" that Afghanistan would continue to detain those prisoners viewed as most dangerous by the United States.

"As of today, we don't have prisoners," Secretary of State John Kerry said on Monday. "Whatever is occurring here is under the control of the Afghan people." But Kerry forgot to mention that we didn't turn all detainees over to the Afghans: the Washington Post reports that even with the nominal transfer of Parwan to Afghan control, the United States continues to detain several dozen Afghan nationals deemed to pose "enduring security threats," along with a similar number of non-Afghan detainees (from Yemen, Pakistan, and elsewhere).

What will we do with the hundred or so Parwan detainees we're not willing to hand over to the Afghans? No one knows -- any more than anyone knows what we'll do with the more than 150 men who remain in detention at Guantánamo.

As with the remaining Parwan detainees, it's hard to pin down the precise numbers, identities, or status of men still held at Guantánamo, but they are divided into at least three general categories. First, there is a small number of detainees held pending military commission trials. Second, there are several dozen detainees who have been "cleared for transfer" or release, but who continue to languish at Guantánamo either because no country, including the United States, is willing to accept them inside its borders, or because the United States is not satisfied that -- you guessed it -- detainees won't "return to the fight" if transferred, say, to Yemen. Finally, there are several dozen detainees who are being held indefinitely, on the grounds that "evidentiary problems" (read: past torture and/or U.S. anxiety about revealing intelligence sources and methods) make it impossible for them to be put on trial, but they're just "too dangerous" to release.

Just as in the Afghan context, however, fears about detainee recidivism are almost certainly overblown. For one thing, most previously released Guantánamo detainees have not "returned to the battlefield" -- and of those who have, few appear to have posed a direct or severe threat to the United States. In a 2011 analysis, for instance, Peter Bergen, Katherine Tiedmann, and Andrew Lebovich found that U.S. government claims about Guantánamo recidivism rates often lumped together anti-U.S. activities with militant activities not directed at the United States.

As a result, they argue, the true rate of anti-U.S. recidivism was probably one-in-seventeen, not one-in-four as claimed at the time by U.S. government sources. And Bergen and his colleagues don't differentiate between abstract "dangerousness" of post-Guantánamo activities and actual harm caused by recidivist detainees -- solid information is impossible to obtain, but logically, not all the former detainees who seek to harm the United States will in fact achieve their goals. (Bergen and company do note, dryly, that the Guantánamo recidivism rate looks, by any measure, a whole lot better than the recidivism rate for criminals incarcerated in U.S. prisons: One U.S. study found that nearly two-thirds of released prisoners were ultimately rearrested.)

If we were to think rationally about closing Guantánamo -- I know, not likely -- we would evaluate several factors with regard to potential detainee releases. First, we'd ask how likely it is that a detainee would seek to "rejoin the fight" in one way or another. Second, we'd ask what level of hazard would likely be posed by recidivism: Would we simply have created yet another low-level Taliban or al Qaeda operative, or do we believe a detainee, if released, would be in a position to cause truly grave harm to the United States? Third, we'd ask whether we can mitigate any risk of harm (more on this in a moment). And fourth, we'd ask ourselves some tough questions about the dangers of holding onto detainees indefinitely.

Here again, perhaps even more than in the Afghan context, we should weigh the potential dangers of releasing detainees against the potential long-term threat posed to the United States by our own detention policies. As in Afghanistan, it's hard to entirely unravel overseas anger at U.S. detention policy from anger at other U.S. policies: globally, these likely include U.S. drone strikes, past interrogation policy, or other issues. Nonetheless, there's ample reason to believe that U.S. detention policies have incited anti-American sentiment around the globe.

Our government seems generally averse to engaging in the serious cost-benefit analysis of our detention policies I have suggested here. (It seems similarly averse to engaging in such a cost-benefit analysis of targeted killings.) Congress and the executive branch share the blame for this, but we shouldn't be terribly surprised: For a nation that prides itself on hard-headed capitalist realism, we Americans often seem wholly unable to conduct the most basic risk assessments. In other words: We're routinely irrational when it comes to risk perception.

There's a vast literature on risk perception and risk management. In theory, people should compare risks by evaluating both the probability of a negative event and the potential magnitude of its consequences. In practice, people have trouble accurately assessing either probabilities or consequences: we are often overly influenced by the perceived novelty of dangers, for instance. Similarly, we tend to be less troubled by risks that we believe we can control: Thus, we worry more about plane crashes (low probability, but once you're buckled into your miserable coach class seat, you have zero control) than car crashes (high probability, but if you're at the wheel, you're likely to place excessive faith in your ability to avoid dangers).

This suggests, however, another potential basis for reconsidering our collective fear that released detainees will return to the battlefield. Although we tend to overlook it, we have the ability to significantly control and mitigate the risk posed by released detainees. For one thing, we have the ability to closely monitor released detainees, using a wide range of surveillance technologies -- thus drastically reducing the likelihood of nasty surprises.

We also have the ability to dramatically reduce the likelihood that a released detainee will be welcomed back into the fold by his former comrades. The credibility of released detainees is already low, since their former colleagues are apt to assume they've been compromised. We can make their credibility lower still.

So here's my idea: Have CIA Director John Brennan fly down to Guantánamo with a retinue of news media from all over the world. As the cameras roll, Brennan should hand every last Guantánamo detainee a U.S. passport and ten thousand bucks. (For Khalid Sheik Mohammed, and other high-value detainees, double or triple that figure.) Brennan should hug the detainees, apologize for the inconvenience caused by 10 years in detention, and thank them profusely for everything they've done to help the United States eliminate al Qaeda and its associates.

And then...we should let them go wherever they want. Yemen? Pakistan? Sure, we'll fly them there first class (and monitor every breath they take, every step they take, every call they make, and so on -- wouldn't it be useful to see who they contact?).

With a send-off like that, we can be pretty sure of one thing. Some detainees may want to return to the battlefield...but the battlefield won't be wanting them back.