Defense spending by the United States accounted for nearly 40 percent of military expenditures by countries around the world in 2023, according to recently released figures from the Stockholm International Peace Research Institute (SIPRI). U.S. defense spending increased by $55 billion from 2022 to 2023, in part due to additional military aid sent to support Ukraine in its ongoing conflict. The United States spends more on defense than the next nine countries combined.
SIPRI’s definition of defense spending is broader than the definitions that are most frequently used in fiscal policy discussions in the United States, and according to their calculations, the United States spent $916 billion on national defense in 2023. SIPRI includes discretionary and mandatory outlays by the Department of Defense, Department of Energy, Department of State, and the National Intelligence Program. By contrast, the national defense budget function ($820 billion in 2023) excludes outlays by the Department of State and certain programs of the Department of Energy. Nonetheless, the SIPRI comparison provides useful insights on the sheer scale of U.S. defense spending relative to other nations.
Although the United States spends more on defense than any other country, the Congressional Budget Office projects that defense spending as a share of gross domestic product (GDP) will decline over the coming years — from 2.9 percent of GDP in 2024 to 2.5 percent in 2034. That is considerably lower than the 50-year average spending on defense of 4.2 percent of GDP.
Defense spending accounts for a sizable portion of the federal budget and the United States vastly outspends other nations. In determining the appropriate level of such spending in the future, it will be important to evaluate whether it is being used effectively and how it fits in with other national priorities.
Infographic: The Facts About U.S. Defense Spending
Related: Budget Basics: National Defense