Research by the Costs of War project, a Corporation grantee, reveals the ongoing costs of the U.S. post-9/11 wars, from human lives and the U.S. global military footprint to internal and external displacement
By
Carnegie Corporation of New York
September 13, 2023
A grantee of Carnegie Corporation of New York, the Costs of War project uses research and a public website to facilitate debate about the costs of the post-9/11 wars in Iraq and Afghanistan, and related violence in Pakistan, Somalia, Syria, and elsewhere. There are many hidden or unacknowledged costs of the United States’ decision to respond to the 9/11 attacks with military force. The project aims to foster democratic discussion of these wars by providing the fullest possible account of their human, economic, environmental, and political costs, and to foster better informed public policies. Created in 2010 and housed at Brown University’s Watson Institute for International and Public Affairs, the Costs of War project builds on the work of over 60 scholars, human rights and legal experts, and physicians from around the world.
Hate breeds hate, quarrel breeds quarrels, war breeds war — a hateful progeny. It is the poorest of all remedies. It poisons as it cures.
Andrew Carnegie, A League of Peace. A Rectorial Address Delivered to the Students in the University of St. Andrews 17th October, 1905
“There are reverberating costs, the human cost of war, that people in the U.S., for the most part, don’t really know or think enough about,” said Stephanie Savell, codirector of the Costs of War project. “We hear talk about the endless war being over now that U.S. troops have left Afghanistan, but one significant way that these wars are continuing is that the people in the war zones are continuing to suffer the consequences. The U.S. has been involved in these really violent wars. There’s been an intensification as a result of U.S. involvement. And at this point, the issue is really: How do we come to terms with a sense of responsibility?”
The Costs of War Project: Goals
To account for the wars’ costs in human lives and the consequences for public health and well-being, both in the U.S. and in the war zones
To assess the wars’ budgetary costs, including the financial legacy, as well as the opportunity costs of the U.S. military budget
To describe the scope of the U.S. global military footprint and its political and social impact in the U.S. and around the world
To examine the environmental and ecological impact of the U.S. global military presence, including military carbon emissions
To evaluate alternatives that provide for meaningful, just, and inclusive human safety and security
Here follow six sections — covering war-related deaths (direct and indirect); human displacement (external and internal refugees); the geographic reach of U.S. counterterrorism activities; Afghanistan before and after the U.S. withdrawal; and the budgetary costs of the U.S. post-9/11 wars — that give a data-rich snapshot of the comprehensive nature of the work undertaken by the Costs of War team. As Neta C. Crawford, Costs of War cofounder and codirector and Montague Burton Professor of International Relations at the University of Oxford, puts it, “It’s hard to convey the cost in lives because of these wars. It’s very tough to talk about it. But we have to.”
The violence stemming from conflicts in Afghanistan, Pakistan, Iraq, Syria, Yemen, and other areas has directly resulted in the deaths of approximately 905,000 to 940,000 people. Several times as many more have been killed as reverberating effects of the wars, losing their lives due to water loss, sewage and other infrastructural issues, and war-related disease.
As with most wars, we may never know the full extent of the loss of life and injuries. The direct effects include the hundreds of thousands of people who have been killed and injured due to the fighting — killed by bombs, bullets, and fire. The number of people killed directly in the violence of the post-9/11 wars in Afghanistan, Pakistan, Iraq, Syria, Yemen, and other war zones is estimated here.
NOTE: The time periods covered in this table are: Oct. 2001–Aug. 2021 (Afghanistan and Pakistan); Mar. 2003–Mar. 2023 (Iraq); Sept. 2014–Mar. 2023 (Syria/ISIS); Oct. 2002–Aug. 2021 (Yemen); and Oct. 2001–Dec. 2014 (other post-9/11 war zones). The chart also draws on another, earlier paper (September 1, 2021) by Neta C. Crawford and Catherine Lutz for the rest of the war zones: Human Cost of Post-9/11 Wars: Direct War Deaths in Major War Zones.
Indirect Deaths: The Reverberating Impact of the Post-9/11 Wars
The number of people killed indirectly in post-9/11 war zones, including in Afghanistan, Pakistan, Iraq, Syria, and Yemen, is estimated at 3.6–3.8 million, though the precise figure remains unknown.
The report How Death Outlives War (May 15, 2023) reviews the latest research to examine the causal pathways that have led to an estimated 3.6–3.8 million indirect deaths in post-9/11 war zones, including Afghanistan, Pakistan, Iraq, Syria, and Yemen. With direct deaths, the total death toll in these war zones could be at least 4.5–4.7 million and counting, though the precise mortality figure remains unknown. Some people were killed in the fighting, but far more, especially children, have been killed by the reverberating effects of war, such as the spread of disease.
The report examines the devastating toll of war on human health, whoever the combatant, whatever the compounding factor, in the most violent conflicts in which the U.S. government has been engaged in the name of counterterrorism since September 11, 2001. Rather than teasing apart who or what is to blame, or separating out the negative enduring effects of prior wars and sanctions, this report shows that the post-9/11 wars are implicated in many kinds of deaths.
In laying out how the post-9/11 wars have led to illness and indirect deaths, the report’s goal is to build greater awareness of the fuller human costs of these wars and support calls for the United States and other governments to alleviate the ongoing losses and suffering of millions in current and former war zones. The report highlights many long-term and underacknowledged consequences of war for human health, emphasizing that some groups, particularly women and children, suffer the brunt of these ongoing impacts.
Indirect war deaths are caused by economic collapse, food insecurity, the destruction of public services and health infrastructure, environmental contamination, reverberating trauma and violence, and other impacts. Furthermore, internal displacements increase people’s vulnerability to the negative health effects of war — including malnutrition, maternal and newborn complications, injury, and disease — which disproportionately impact women and children.
Millions Displaced by the Post-9/11 Wars
Over 38 million people have been displaced — becoming refugees seeking safety in another country, or becoming internally displaced within their own country — as a result of the wars the U.S. military has fought since 2001. That is more than those displaced by any war or disaster since the start of the 20th century, except for World War II. Although the United States has accepted hundreds of thousands of refugees, most have been hosted by countries in the greater Middle East.
Any number is limited in what it can convey about displacement’s damage. The people behind the numbers can be difficult to see, and numbers cannot communicate how it might feel to lose one’s home, belongings, community, and much more. Displacement has caused incalculable harm to individuals, families, towns, cities, regions, and entire countries physically, socially, emotionally, and economically.
In this map, arrows point to the top three countries where the most refugees and asylum seekers from each war-affected country have fled as of 2019. Arrows for Syria include all displaced Syrians, 2011–2019.
Dates indicate the start of U.S. military involvement. Displaced persons data updated through 2020; Syrian and Afghan internally displaced persons data updated through 2021. Syrian data only includes people displaced during years of direct U.S. military involvement in the war and in five provinces where U.S. forces have fought. Key source, updated August 2021: David Vine, Cala Coffman, Katalina Khoury, Madison Lovasz, Helen Bush, Rachel Leduc, and Jennifer Walkup, Creating Refugees: Displacement Caused by the United States’ Post-9/11 Wars, Costs of War Project, Brown University, Sept. 21, 2020. (Credit: Map and graphics by Kelly Martin, www.kmartindesign.com & Investigative Reporting Workshop)
The U.S. government has taken part in what it has labeled “counterterrorism” activities in at least 85 countries, in an outgrowth of President George W. Bush’s “Global War on Terror” and the U.S. invasion of Afghanistan in 2001.
The map below illustrates countries in which the U.S. government conducted operations it explicitly described as counterterrorism, in an outgrowth of President George W. Bush’s “Global War on Terror.” These operations included air and drone strikes; on-the-ground combat; so-called “Section 127e” programs in which U.S. special operations forces support “foreign forces, irregular forces, groups, or individuals” engaged in counterterrorism activities; military exercises in preparation for or as part of counterterrorism missions; and operations to train and assist foreign forces. The map does not comprehensively cover the full scope of U.S. post-9/11 warfare, as it does not document, for instance, U.S. military bases used for counterterror operations, arms sales to foreign governments, or all deployments of U.S. special operations forces.
Despite the Pentagon’s assertion that the U.S. is shifting its strategic emphasis away from counterterrorism and toward great power competition with Russia and China, examining U.S. military activity on a country-by-country basis shows that there is yet to be a corresponding drawdown of the counterterror apparatus. If anything, this map demonstrates that counterterrorism operations have become more widespread in recent years.
Afghanistan Before and After 20 Years of War (2001—2021)
Examining data before the U.S. war in Afghanistan and after the U.S. withdrawal, the infographic below displays indicators of poverty, food insecurity, child malnutrition, women’s rights, U.S. spending, and more.
After the war, Afghanistan has seen increases in the percentage of Afghans facing food insecurity, children under five experiencing acute malnutrition, and Afghans living in poverty. Women's rights continue to be heavily restricted. U.S. development aid to Afghanistan has amounted to $36.07 billion since 2001, while U.S. spending on the top five military contractors has amounted to $2.1 trillion. In 2022, there were 1.5 million Afghans living with physical disabilities and 2 million Afghan widows.
Go Deeper
To learn more, check out the list of sources & download a PDF of the infographic.
Estimate of U.S. Post-9/11 War Spending FY2001–FY2022
The vast economic impact of the post-9/11 wars in Afghanistan, Pakistan, Iraq, Syria, and elsewhere is poorly understood by the U.S. public and policymakers.
The economic impact of the U.S. post-9/11 wars extends beyond the Pentagon’s “Overseas Contingency Operations” (war) budget. The charts below and the paper The U.S. Budgetary Costs of the Post-9/11 Wars (September 1, 2021) estimate the more comprehensive budgetary costs of the wars, including past expenditures and future obligations to care for veterans of these wars.
The comprehensive budgetary costs of the U.S. post-9/11 wars include overseas contingency operations (OCO) of the Department of Defense ($2,101 billion), homeland security prevention and response to terrorism ($1,117 billion), interest on OCO borrowing ($1,087 billion), increases to Department of Defense base budget ($884 billion), veterans’ medical care and disability ($465 billion), and State Department OCO appropriations ($189 billion).
Including estimated future costs for veterans’ care, the total budgetary costs and future obligations of the post-9/11 wars is about $8 trillion in current dollars.
Concept by Kenneth Benson and Daniel Um. Art Direction by Daniel Um. Text by the Costs of War project. Kenneth Benson is Carnegie Corporation of New York’s editorial manager. Daniel Um is Carnegie Corporation of New York’s principal design director.
Deana Arsenian reflects on the ways the Corporation’s International Program advances knowledge and understanding of issues, regions, and countries as an essential — if imperfect — element of its efforts to reduce global threats and promote cooperative approaches to security challenges
