America’s war on terror has now entered its seventeenth year. The U.S. has invaded Afghanistan and Iraq and conducted military operations in Pakistan, Syria, Yemen, Somalia, Libya, and the Philippines. More recently, four military members died in Niger during an ambush, suggesting the war on terror continues to widen.

The war has cost the lives of nearly 7,000 service members and between $1.8 and $4 trillion. Despite the heavy toll in blood and treasure, most Americans seem content for the war to continue. Polling indicates 70 percent of Americans believe an attack that will kill “large numbers of lives” is somewhat or very likely in the near future, just under six in ten say Islamic fundamentalism is a critical and enduring threat to the country, and 41 percent think the U.S. is winning the war (as opposed to 17 percent who think the terrorists are).1

I argue that the war endures, in large part, because national security policy makers, military operators, and think tank scholars have embraced several false assumptions. The first two help explain why the U.S. continues to fight, while the third spells out why the problem will persist regardless of whether the U.S. fights or not. Policy makers, operators, and scholars falsely assume that the war on terror has prevented another 9/11. Additionally, they imagine that U.S. military operations have more broadly reduced the threat to Americans and the homeland. The final flawed assumption—in war, mental health only matters when it affects U.S. service members—implicitly informs U.S. strategy and highlights why Afghanistan’s war will not end anytime soon. 

False Assumption #1: The War on Terror Prevented Another 9/11

Nothing like the attacks of 11 September had ever occurred before 2001 or since. By virtue of being unprecedented, those attacks would be almost impossible to repeat. The world’s second worst attack, for instance, killed just half as many people and it occurred in war-torn Iraq. And it is in conflict-affected or failed states where virtually all significant terror attacks happen. The third worst event took place in Rwanda during their 1994 genocide. By the fourth most catastrophic incident, not even a quarter as many people died as compared to 9/11. For the remaining 10 most horrific terror attacks, two each occurred in Iraq and Syria and one each in the Democratic Republic of the Congo, Nepal, and Iran (during their 1978 revolution).2

Of the ten worst attacks in the past 45 years, only 9/11 occurred outside of a war zone. In addition, all of those mass-casualty terror strikes killed substantially fewer people than Mohamed Atta and his con-conspirators did on September 11th. As the recent spate of attacks involving trucks plowing into crowds suggests, killing lots of people in a single attack is very difficult.

A dispassionate analysis of the data does not change the horror of terrorism or the pain and loss caused by even one death, but it should drive home the point that 9/11 was an outlier both in terms of lives lost and where it occurred. And its outlier status strongly suggests another 9/11-type event in the U.S. was a near impossibility even before America launched its expansive war on terror.

Curiously, while the attacks of September 11th were unprecedented, success did not require a large terror network. Nineteen men executed the mission. Financial costs were minimal, consisting of several pilot training slots and airfare for the attackers. The technical training required for mission success took place in plain sight here in the United States, not in some clandestine Afghan training camp. All the terrorists legally entered the country through the Visa system. One of the pilots lived with his flight instructors. After departing the U.S. for vacation, two successfully argued their way back into the country by assuring American agents that they were authorized to be here on student visas, specifically so they could attend pilot training school.3 The genius of the attack did not derive from any organizational structure or material largesse, rather it originated within a creative and visionary mind that foresaw an attack method never before attempted and that only Tom Clancy had apparently conceived of in his fictional work, Debt of Honor.

If the preceding argument is correct, the burden of proof shifts to proponents of the claim that U.S. combat operations have prevented another 9/11. They should be called on to lay out an argument of how U.S. military force has managed to prevent a small group of like-minded men from again coming together and launching a mega-attack. Additionally, defenders of such a claim should explain how air strikes and invasions have wiped out terror finances to the point that groups like al Qaeda and the Islamic State can no longer fund a handful of pilot school slots (or whatever their current modus operandi might be).

The most obvious arguments for why another 9/11 has not taken place, then, seem to be 1) the already discussed point that such an unprecedented attack, by definition, cannot be easily replicated and 2) homeland security efforts have been quite successful. After 9/11, the U.S. government ushered in dramatic changes, creating the Department of Homeland Security in the “largest reorganization in the United States government since World War II.” The FBI substantially shifted its focus from “traditional criminal investigative areas” to making “the prevention of another terrorist attack” its top priority. Congress passed The USA Patriot Act and other legislation to facilitate intelligence gathering and sharing on potential terror threats. And, financial costs for homeland security rose an estimated $800 billion.4

And those efforts have worked. The Heritage Foundation reports that while Islamist-inspired terrorists have plotted at least 101 attacks against the homeland since 2001, law enforcement thwarted virtually all of them. In those 16 years, Islamist-inspired terrorists have only managed to execute a successful attack every two years, on average, killing fewer than six per year. That represents less than 0.0004 percent of all American murder victims during the same period. Even lightning has averaged nearly three times as many fatalities.5 And, none of those who carried out these more recent attacks fit the 9/11 terrorist profile. Instead, they were all either U.S. citizens or they had become radicalized after coming to America. 

False Assumption #2: Military Operations Have Reduced the Terror Threat

The number of Islamist-inspired terror groups and their associated fighters have substantially increased since 9/11, and the increase appears to be in response to U.S. military operations rather than despite them. In Iraq, for instance, U.S. forces failed to restore the state’s monopoly on the use of force after removing it during the invasion. That misstep created the opportunity for an explosive civil war. In Afghanistan, the effect was not as severe, but after the U.S. invasion, the security situation did deteriorate back to pre-Taliban levels.

In the five years before 2001, al Qaeda and the 13 like-minded groups identified by the Department of State averaged approximately 32,000 total adherents. In the 16 years since, those numbers have jumped to an estimated 44 groups with more than 109,000 members (despite the U.S. military claiming to have killed more than 60,000).6 At least three factors likely explain this counterintuitive finding:

McChrystal Math

In 2003, then-Secretary of Defense Donald Rumsfeld asked whether “we [are] capturing, killing, or deterring and dissuading more terrorists every day than the madrassas and the radical clerics are recruiting, training and deploying against us.” Six years later, General McChrystal offered an answer: “Let us say that there are 10 [insurgents] in a certain area. Following a military operation, two are killed. How many insurgents are left? Traditional mathematics would say that eight would be left, but there may only be two, because six of the living eight may have said, ‘This business of insurgency is becoming dangerous so I am going to do something else.’ There are more likely to be as many as 20, because each one you killed has a brother, father, son and friends, who do not necessarily think that they were killed because they were doing something wrong. It does not matter – you killed them. Suddenly, then, there may be 20, making the calculus of military operations very different.”7 That does not mean some terrorists and insurgents don’t need to die, but it makes clear that in fights like this one, the calculus is not so simple. One kill does not bring America one terrorist closer to victory.

No Monopoly on the Use of Force

U.S. military operations unwittingly degraded the host-nation governments’ monopoly on the use of force in Iraq and, to a lesser extent, Afghanistan, Libya, and Syria. As a result, terror groups have benefitted from the increase in ungoverned spaces and the states’ incompetent security forces. The Afghan government, for instance, barely controls or influences half of the country despite a defense and security force of nearly 365,000. Conversely, before sent fleeing by U.S. forces, the Taliban controlled or influenced 90 percent of the country with just an estimated 35,000 forces.8

The security studies literature indicates that civil wars occur where the opportunity for rebellion exists. For example, ineffective or non-existent security forces increase the opportunity for civil war because their failure to monopolize the use of force increases rebel viability, making it more likely rebels will initiate attacks against their government.9

Terror Recruitment Fueled by U.S. Military Strikes

As part of the war on terror, America has conducted military operations in at least eight Muslim-majority countries: Afghanistan, Iraq, Pakistan, Syria, Libya, Yemen, Somalia, and Niger. Polling clearly shows the use of U.S. military force has inflamed grievances among Muslims. A survey of 11 Muslim-majority populations, for example, found that more respondents agreed than disagreed with the statement, “The United States’ interference in the region justifies armed operations against the United States everywhere.” That trend even held true among the citizens of supposed U.S. allies like Kuwait, Jordan, and Iraq. Osama bin Laden expressed the roots of this sentiment back in the 1990’s. He referred to the “American crusader forces” and “American occupiers,” as he railed against the U.S. presence in Saudi Arabia, home to Islam’s two holiest sites. Later, in the midst of the Iraq war, his deputy, Ayman al-Zawahiri, echoed that sentiment as he exhorted a subordinate leader, “The Muslim masses…do not rally except against an outside occupying enemy, especially if the enemy is firstly Jewish, and secondly American.”10

False Assumption #3: Mental Health Doesn’t Matter (Except for Returning U.S. Service Members)

It is ironic that the U.S. military has paid so much attention to the mental health of returning veterans, while ignoring trauma’s effects on allied foreign populations and how those effects might impact their governing and warfighting capacity. Joint doctrine on counterinsurgency notes that the current war has “the population as its focus of operations.” In recognition of the population’s importance, America’s warfighters have tried to learn the history, cultural norms, and languages of countries like Iraq and Afghanistan. General Petraeus emphasized the point, noting that “the human terrain is the decisive terrain.”11 Yet, despite the evidence suggesting its likely impact on the war, the mental health status of those populations has gone unexamined.

Here is the basic argument: more exposure to traumatic events like war, torture, and rape results in more mental illness, substance abuse, and diminished impulse control. Taken together, mental illness, substance abuse, and diminished impulse control make people more violent, more aggrieved, and less capable. While this may sound new and controversial to warfighters, mental health and trauma scholars have been talking about these linkages for decades.12 

In the case of Afghanistan, studies indicate 29 to 50 percent of the population currently suffer from PTSD. And when you add in depression, the numbers may rise as high as 68 percent. Because of all the torture, rape, war, and domestic violence that Afghans have been subjected to over the past 40 years, not only do they suffer from substantially elevated mental illness rates, but they are also afflicted by substance abuse problems twice the global average and climbing, as well as diminished impulse control. An example of the latter occurred in 2010 during my military service there. An argument erupted between two Afghan colonels in their operations center. The colonel we all loved because of his bravery proved no rhetorical match for his counterpart. However, instead of ending the argument or walking away, he unholstered his sidearm and drew down on the other Afghan colonel. Thankfully, an American military officer was nearby and literally stepped between the two Afghans and prevented the potential loss of life. 

When combined, more mental illness, substance abuse, and impulse control problems make Afghans more likely to use violence against one another to resolve problems and achieve their goals. No wonder, then, that more than half of surveyed Afghans indicated they have been the victim of assaultive violence versus a paltry four percent of the populations in low trauma nations.13

When U.S. service members fighting in the war on terror show signs of mental health problems, many actions are taken. First, they are removed from the trauma environment. Then, they receive the needed medical care, which may include prescription drugs. Additionally, their military responsibilities are curtailed for a time, so they can focus on recovery and avoid adding unnecessary stress into their lives. Finally, a commander might temporarily revoke their authority to bear arms to minimize the threat they could pose to themselves or others.14

But Afghans, Iraqis, and others caught in the war on terror face just the opposite reality. Extremely high rates of trauma continue, and they have no reasonable chance of treatment. For instance, experts describe Afghanistan’s mental health capability as “nonexistent,” qualified providers as “an acute shortage,” and in general terms, “chronic mental illness has been left unattended in Afghanistan for decades.”15 In addition, America and the international community placed additional responsibilities on Afghans, which likely added to their stress. Specifically, the international community pushed democracy on Afghanistan, arguably the best yet hardest form of government to do right. To succeed, democracy requires a legitimate, capable, and responsive government and an engaged populace. After 40 years of the severest traumas, Afghans’ abilities are so reduced and their society too fractured for such a demanding form of government. No surprise, then, that the Afghan government ranks as more corrupt than 96 percent of all other nations and the country receives Freedom House’s lowest rating—“not free.”16

In response to all the trauma and the negative changes which often accompany it, Afghans should be expected to resort to violence as a means of goal achievement and problem resolution more often than a low trauma population. In addition to making people more violent, all the trauma likely fuels more civil war in two other ways: by increasing grievances and creating more opportunity for civil war.17 A person who has been tortured, raped, or exposed to war violence has, by definition, a very real and enduring grievance against the perpetrator or the group that the perpetrator belongs to. Civil war scholars have long believed that grievances are what motivate citizens to organize and take up arms against their government.

Trauma should also increase the opportunity for civil war by making the government and security forces less effective. For instance, severe and repetitive trauma exposure often leads to mental illness, substance abuse, and physiological changes to parts of the brain (e.g., amygdala, basal ganglia). In turn, those three factors conspire to lower individual IQ, diminish the ability to reason and plan, decrease attention span, and reduce the capacity for trust.18 A government and security force increasingly forced to recruit from such a population will become less effective over time, and ineffective security forces make civil war more possible.

Conclusion

The war on terror has now entered its seventeenth year. Military operations appear to have expanded into Niger and potentially other countries. Forces are surging back into Afghanistan and an indefinite military presence in Syria appears to be current U.S. policy. All of this appears to be driven, in large part, by three false assumptions. In reality, though, the war on terror has done little to prevent another 9/11, and all of the military force employed abroad has not made Americans any safer. That suggests the United States should step back from the war on terror by ratcheting down the use of military force abroad, while emphasizing internal homeland security measures and external intelligence sharing.

Finally, the years of trauma have taken their toll on Afghans, Iraqis, and others, resulting in extremely high rates of mental illness, substance abuse, and diminished impulse control. And those factors will likely fuel civil war into the future, whether the United States stays in the fight or not.

End Notes

1. See, for example, polls and surveys from the Chicago Council, Rasmussen Reports, and Polling Report available at http://​www​.pollingre​port​.com/​t​e​r​r​o​r.htm, http://​www​.ras​mussen​re​ports​.com/​p​u​b​l​i​c​_​c​o​n​t​e​n​t​/​p​o​l​i​t​i​c​s​/​m​o​o​d​_​o​f​_​a​m​e​r​i​c​a​/​w​a​r​_​o​n​_​t​e​r​r​o​r​_​nov08, and https://www.thechicagocouncil.org/sites/default/files/survey_terror-acts-and-americans_20160822‑2.pdf.

2. Data comes from the Global Terrorism Database, available at https://​www​.start​.umd​.edu/gtd/.

3. As noted in the National Commission on Terrorist Attacks upon the United States’ report, 9/11 and Terrorist Travel, the hijackers entered the United States with approved visas, though some provided false information or employed other fraudulent techniques, https://www.9–11commission.gov/staff_statements/911_TerrTrav_Monograph.pdf;

9/11 Commission, The 9/11 Commission Report (Washington, D.C.: Government Printing Office, 2004) 224, 227–229, https://9–11commission.gov/report/911Report.pdf.

4. Elizabeth Bazan, The Foreign Intelligence Surveillance Act: An Overview of the Statutory Framework and U.S. Foreign Intelligence Surveillance Court and U.S. Foreign Intelligence Surveillance Court of Review Decisions (Washington, D.C.: Congressional Research Service, [updated] 2017), https://​fas​.org/​s​g​p​/​c​r​s​/​i​n​t​e​l​/​R​L​3​0​4​6​5.pdf; Watson Institute – Brown University, “Homeland Security Budget,” Costs of War, September 2016, http://​wat​son​.brown​.edu/​c​o​s​t​s​o​f​w​a​r​/​c​o​s​t​s​/​e​c​o​n​o​m​i​c​/​b​u​d​g​e​t/dhs; Neta Crawford, United States Budgetary Costs of Post‑9/​11 Wars Through, Costs of War Project, 2017, http://watson.brown.edu/costsofwar/files/cow/imce/papers/2017/Costs%20of%20U.S.%20Post-9_11%20NC%20Crawford%20FINAL%20.pdf pp. 2–3; Department of Justice, The External Effects of the Federal Bureau of Investigation’s Reprioritization Efforts (2005), iii, https://​oig​.jus​tice​.gov/​r​e​p​o​r​t​s​/​F​B​I​/​a​0​5​3​7​/​f​i​n​a​l.pdf; Robert Mueller, “Testimony Before the House Appropriations Subcommittee on Science, the Departments of State, Justice and Commerce, and Related Agencies,” September 14, 2006, https://​archives​.fbi​.gov/​a​r​c​h​i​v​e​s​/​n​e​w​s​/​t​e​s​t​i​m​o​n​y​/​t​h​e​-​f​b​i​-​t​r​a​n​s​f​o​r​m​a​t​i​o​n​-​s​i​n​c​e​-2001

5. David Inserra, “Foiled Plot in Miami Is 99th Terror Plot Against US Since 9/11,” November 1, 2017,http://​www​.her​itage​.org/​t​e​r​r​o​r​i​s​m​/​c​o​m​m​e​n​t​a​r​y​/​f​o​i​l​e​d​-​p​l​o​t​-​m​i​a​m​i​-​9​9​t​h​-​t​e​r​r​o​r​-​p​l​o​t​-​a​g​a​i​n​s​t​-​u​s-911; A. Trevor Thrall and Erik Goepner, “Step Back: Lessons for U.S. Foreign Policy from the Failed War on Terror,” Cato Institute Policy Analysis #814 (Washington, D.C.: Cato Institute, 2017), 6, https://​object​.cato​.org/​s​i​t​e​s​/​c​a​t​o​.​o​r​g​/​f​i​l​e​s​/​p​u​b​s​/​p​d​f​/​p​a​-​8​1​4.pdf; and Laura Geggel, “Lightning deaths hit a record low in 2017,” Fox News, January 3, 2018, http://​www​.foxnews​.com/​s​c​i​e​n​c​e​/​2​0​1​8​/​0​1​/​0​3​/​l​i​g​h​t​n​i​n​g​-​d​e​a​t​h​s​-​h​i​t​-​r​e​c​o​r​d​-​l​o​w​-​i​n​-​2​0​1​7​.html.

6. A. Trevor Thrall and Erik Goepner, “Counterinsurgency Math Revisited,” Small Wars Journal Blog, January 3, 2018, http://​small​warsjour​nal​.com/​b​l​o​g​/​c​o​u​n​t​e​r​i​n​s​u​r​g​e​n​c​y​-​m​a​t​h​-​r​e​v​i​sited, derived from Department of State Country Reports on Terrorism 2000 through 2015 and Stanford University’s Mapping Militant Organizations Project.

7. Donald Rumsfeld, “Global War on Terrorism,” memo to select Department of Defense leaders, October 16, 2003, https://​fas​.org/​i​r​p​/​n​e​w​s​/​2​0​0​3​/​1​0​/​r​u​m​s​f​e​l​d​1​0​1​6​0​3.pdf; Stanley McChrystal, “Speech on Afghanistan,” delivered before the International Institute for Strategic Studies, London, United Kingdom, October 1, 2009, https://​www​.real​clear​pol​i​tics​.com/​a​r​t​i​c​l​e​s​/​2​0​0​9​/​1​0​/​0​1​/​g​e​n​_​m​c​c​h​r​y​s​t​a​l​s​_​a​d​d​r​e​s​s​_​o​n​_​a​f​g​h​a​n​i​s​t​a​n​_​9​8​5​3​7​.html.

8. Bill Roggio and Alexandra Gutowski, “LWJ Map Assessment: Taliban Controls or Contests 45% of Afghan Districts;” Erik Goepner, “Afghanistan’s Biggest Obstacle is Its Government,” Orange County Register (November 1, 2017), https://​www​.ocre​g​is​ter​.com/​2​0​1​7​/​1​1​/​0​1​/​a​f​g​h​a​n​i​s​t​a​n​s​-​b​i​g​g​e​s​t​-​o​b​s​t​a​c​l​e​-​i​s​-​i​t​s​-​g​o​v​e​r​n​ment/; and Freedom House, Freedom in the World 2001 and Freedom in the World 2017 (2001 and 2017), https://​free​dom​house​.org/​r​e​p​o​r​t​-​t​y​p​e​s​/​f​r​e​e​d​o​m​-​world.

9. Paul Collier, Anke Hoeffler, and Dominic Rohner, “Beyond Greed and Grievance: Feasibility and Civil War,” Oxford Economic Papers 61.1 (2009): 1–27; James Fearon and David Laitin, “Ethnicity, Insurgency, and Civil War,” American Political Science Review 97.1 (2003): 75–90.

10. See the Arab Barometer http://​www​.arab​barom​e​ter​.org/​c​o​n​t​e​n​t​/​o​n​l​i​n​e​-​d​a​t​a​-​a​n​a​lysis, FBIS, “Compilation of Usama Bin Laden Statements: 1994 – January 2004,” January 2004, https://​fas​.org/​i​r​p​/​w​o​r​l​d​/​p​a​r​a​/​u​b​l​-​f​b​i​s.pdf, and Ayman al-Zawahiri’s letter to Abu Mus‘ab al-Zarqawi, https://​ctc​.usma​.edu/​w​p​c​o​n​t​e​n​t​/​u​p​l​o​a​d​s​/​2​0​1​3​/​1​0​/​Z​a​w​a​h​i​r​i​s​-​L​e​t​t​e​r​-​t​o​-​Z​a​r​q​a​w​i​-​T​r​a​n​s​l​a​t​i​o​n.pdf.

11. Joint Staff, Joint Publication 3–24 Counterinsurgency (2013), III‑4, http://​www​.jcs​.mil/​P​o​r​t​a​l​s​/​3​6​/​D​o​c​u​m​e​n​t​s​/​D​o​c​t​r​i​n​e​/​p​u​b​s​/​j​p​3​_​2​4.pdf; Leo Shane III and Kevin Baron, “Petraeus confirmation hearing, live” Stars and Stripes, June 29, 2010, https://www.stripes.com/blogs-archive/stripes-central/stripes-central‑1.8040/petraeus-confirmation-hearing-live‑1.109226#.Wk-oaLenEdU.

12. Chris Brewin et al., “Memory for Emotionally Neutral Information in Posttraumatic Stress Disorder: A Meta-Analytic Investigation,” Journal of Abnormal Psychology 116, no. 3 (2007): 448–63; Pia Pechtel and Diego Pizzagalli, “Effects of Early Life Stress on Cognitive and Affective Function: An Integrated Review of Human Literature,” Psychopharmacology 214.1 (2011): 55–70 ; Zachary Steel et al., “Association of Torture and Other Potentially Traumatic Events with Mental Health Outcomes among Populations Exposed to Mass Conflict and Displacement,” JAMA 302.5 (2009): 537–549; Darrel Regier, Mary Farmer, and Donald Rae, “Comorbidity of Mental Disorders With Alcohol and Other Drug Abuse: Results From the Epidemiologic Catchment Area (ECA) Study,” JAMA 264, no. 19 (November 21, 1990): 2514; Timothy Weaver et al., “Comorbidity of Substance Misuse and Mental Illness in Community Mental Health and Substance Misuse Services,” The British Journal of Psychiatry 183, no. 4 (September 2003): 304–31.

13. Catherine Panter-Brick et al., “Violence, Suffering, and Mental Health in Afghanistan: A School-Based Survey,” The Lancet 374, no. 9692 (September 2009): 814; Hillary Wildt et al., “War Trauma, Psychological Distress, and Coping among Afghan Civilians Seeking Primary Health Care,” International Perspectives in Psychology: Research, Practice, Consultation 6, no. 2 (April 2017): 82; Annette Gerritsen et al., “Physical and mental health of Afghan, Iranian and Somali asylum seekers and refugees living in the Netherlands,” Social Psychiatry and Psychiatric Epidemiology 41.1 (2006): 18–26; Israel Bronstein, Paul Montgomery, and Stephanie Dobrowolski, “PTSD in Asylum‐​seeking Male Adolescents from Afghanistan,” Journal of Traumatic Stress 25.5 (2012): 551–557; Steel et al. “Association of Torture…”; United Nations Office on Drugs and Crime, “Drug Use in Afghanistan: 2009 Survey. Executive Summary” (Kabul, Afghanistan: UNODC, 2010) 3, 6, http://​www​.unodc​.org/​d​o​c​u​m​e​n​t​s​/​d​a​t​a​-​a​n​d​-​a​n​a​l​y​s​i​s​/​S​t​u​d​i​e​s​/​A​f​g​h​a​n​-​D​r​u​g​-​S​u​r​v​e​y​-​2​0​0​9​-​E​x​e​c​u​t​i​v​e​-​S​u​m​m​a​r​y​-​w​e​b.pdf; Dianne Tice, Ellen Bratslavsky, and Roy Baumeister, “Emotional Distress Regulation Takes Precedence over Impulse Control: If You Feel Bad, Do It!,” Journal of Personality and Social Psychology 80, no. 1 (2001): 53; Michael Norko and Madelon Baranoski, “The Prediction of Violence; Detection of Dangerousness,” Brief Treatment and Crisis Intervention 8, no. 1 (February 2008): 76; Hepp et al., “Prevalence of Exposure to Potentially Traumatic Events and PTSD,” 154; Barbara Lopes Cardozo, “Mental Health, Social Functioning, and Disability in Postwar Afghanistan,” JAMA 292, no. 5 (August 4, 2004) 575, 579; Willem Scholte, Miranda Olff, and Peter Ventevogel, “Mental Health Symptoms Following War and Repression in Eastern Afghanistan,” JAMA 292, no. 5 (August 4, 2004) 589–590.

14. U.S. Department of Veterans Affairs, “How Common is PTSD,” PTSD: National Center for PTSD(October 3, 2016), https://​www​.ptsd​.va​.gov/​p​u​b​l​i​c​/​P​T​S​D​-​o​v​e​r​v​i​e​w​/​b​a​s​i​c​s​/​h​o​w​-​c​o​m​m​o​n​-​i​s​-​p​t​s​d.asp.

15. Cardozo, “Mental Health, Social Functioning, and Disability in Postwar Afghanistan,” 576; Panter-Brick et al., “Violence, Suffering, and Mental Health in Afghanistan,” 813.

16. See Transparency International’s Corruption Perceptions Index at https://​www​.trans​paren​cy​.org/​c​o​u​n​t​r​y/AFG and Freedom House’s Freedom in the World at https://​free​dom​house​.org/​r​e​p​o​r​t​/​f​r​e​e​d​o​m​-​w​o​r​l​d​/​2​0​1​8​/​a​f​g​h​a​n​istan.

17. Fearon and Laitin, “Ethnicity, Insurgency, and Civil War”; Collier, Hoeffler, and Rohner, “Beyond Greed and Grievance,”

18. Brewin et al., “Memory for Emotionally Neutral Information in Posttraumatic Stress Disorder”; Pechtel and Pizzagalli, “Effects of Early Life Stress on Cognitive and Affective Function”; Fu Lye Woon, Shabnam Sood, and Dawson Hedges, “Hippocampal Volume Deficits Associated with Exposure to Psychological Trauma and Posttraumatic Stress Disorder in Adults: A Meta-Analysis,” Progress in Neuro-Psychopharmacology and Biological Psychiatry 34, no. 7 (October 1, 2010): 1181–88; Deborah Weber and Cecil Reynolds, “Clinical Perspectives on Neurobiological Effects of Psychological Trauma,” Neuropsychology Review 14, no. 2 (June 1, 2004): 115–29; Anke Karl et al., “A Meta-Analysis of Structural Brain Abnormalities in PTSD,” Neuroscience & Biobehavioral Reviews 30, no. 7 (2006): 1004–31.