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Updated Cost of War Data Shows U.S. Military Now in 80 Countries


New data from the Costs of War project at Brown University shows that the United States’ war on terror has spread across 40% of the world’s nations. Peace science provides insight into the disastrous human, social, and economic toll war has on all parties involved.

In the News:

“New Costs of War data released today shows that the United States is now combating terrorism in forty percent of the world’s nations. Over 17 years after American and allied troops invaded Afghanistan, launching President George W. Bush’s Global War on Terrorism, this war is not winding down. Instead, it has expanded to 80 countries.  The data is released as a world map in this month’s Smithsonian magazine. To develop the map, a research team led by Stephanie Savell, co-director of Costs of War, combed through U.S. government sources, published and unpublished reports, military websites, and geographical databases; contacted US embassies overseas and the military’s U.S. Africa Command; and conducted inquiries with journalists, academics and others.”

“Covering U.S. activity abroad from 2017 through 2018, this is the second annual update of the map, and it includes four more countries than last year’s version.  The map provides details on five different categories of U.S. activity: military bases or smaller military outposts involved in counterterrorism; direct action and/or combat against militants by U.S. troops; air and drone strikes against terrorist targets; military and/or State Department training or assistance in counterterrorism; and military exercises intended to deter militants and build partnerships to combat terrorism. The map does not include other, additional U.S. military activity aimed at deterring rival powers (Russia and China) or activity characterized as providing humanitarian aid or nation-building.”

“The fourteen countries where the U.S. has engaged in combat were the trickiest to document, for officially, the U.S. military often does not admit to doing anything beyond train and assist missions. Researchers relied on the work of investigative journalists who have shown that in reality, the line between “assistance” and combat is often blurred.  Given the research team’s conservative approach to inclusion of cases, the U.S. war on terrorism is almost certainly more extensive than this data shows.”

Insight from Peace Science:

Vol. 3, Issue 1: Human Rights Implications of Foreign U.S. Military Bases

  • Increased military spending leads to slower economic growth.
  • Over a 20-year period, a 1% increase in military spending will decrease a country’s economic growth by 9%.
  • Increased military spending is especially detrimental to the economic growth of wealthier countries.


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