An American University Brown University’s Watson Institute for International and Public Affairs published its annual “Costs of War” report Wednesday, stating that The United States has spent nearly $6 trillion on wars that directly contributed to the deaths of around 500,000 people since the 9/11 attacks of 2001.

The report took into consideration the Pentagon’s spending and its Overseas Contingency Operations account, as well as “war-related spending by the Department of State, past and obligated spending for war veterans’ care, interest on the debt incurred to pay for the wars, and the prevention of and response to terrorism by the Department of Homeland Security.”

The final count revealed, “The United States has appropriated and is obligated to spend an estimated $5.9 trillion (in current dollars) on the war on terror through Fiscal Year 2019, including direct war and war-related spending and obligations for future spending on post 9/11 war veterans.”
“In sum, high costs in war and war-related spending pose a national security concern because they are unsustainable,” the report concluded. “The public would be better served by increased transparency and by the development of a comprehensive strategy to end the wars and deal with other urgent national security priorities.”

The U.S. embarked on a global war on terror following the 9/11 attacks that killed nearly 3,000 and were orchestrated by Islamist militant group Al-Qaeda. Weeks later, the U.S. led an invasion of Afghanistan, which at the time was controlled by Al-Qaeda ally the Taliban. In March 2003, Washington overthrew Iraqi President Saddam Hussein, accusing him of developing weapons of mass destruction and harboring U.S.-designated terrorist organizations.

Despite initial quick victories there, the U.S. military has been plagued by ongoing insurgencies these two countries and expanded counterterrorism operations across the region, including Libya, Pakistan, Somalia and Yemen. In 2014, the U.S. gathered an international coalition to face the Islamic State militant group (ISIS), which arose out of a post-invasion Sunni Muslim insurgency in Iraq and spread to neighboring Syria and beyond.

Wednesday’s report found that the “US military is conducting counterterror activities in 76 countries, or about 39 percent of the world’s nations, vastly expanding [its mission] across the globe.” In addition, these operations “have been accompanied by violations of human rights and civil liberties, in the US and abroad.”

Overall, researchers estimated that “between 480,000 and 507,000 people have been killed in the United States’ post-9/11 wars in Iraq, Afghanistan, and Pakistan.” This toll “does not include the more than 500,000 deaths from the war in Syria, raging since 2011” when a West-backed rebel and jihadi uprising challenged the government, an ally of Russia and Iran. That same year, the U.S.-led NATO Western military alliance intervened in Libya and helped insurgents overthrow longtime leader Muammar el-Qaddafi, leaving the nation in an ongoing state of civil war.

The combined human cost for the U.S. throughout its actions in Afghanistan, Iraq and Pakistan was 6,951 troops, 21 civilians and 7,820 contractors.

“While we often know how many US soldiers die, most other numbers are to a degree uncertain. Indeed, we may never know the total direct death toll in these wars. For example, tens of thousands of civilians may have died in retaking Mosul and other cities from ISIS but their bodies have likely not been recovered,” the report noted.

“In addition, this tally does not include ‘indirect deaths.’ Indirect harm occurs when wars’ destruction leads to long term, ‘indirect,’ consequences for people’s health in war zones, for example because of loss of access to food, water, health facilities, electricity or other infrastructure,” it added.