How has the percentage of the federal budget allocated to defense spending changed since 2020?

1. The pre-2020 baseline that frames every comparison

The most recent pre-pandemic baseline in the material shows $676 billion on national defense in FY2019, which represented about 15% of total federal expenditures, and contrasted with historically higher shares in earlier decades when defense consumed a much larger slice of federal outlays ^[2]. This baseline is important because percentage shares depend on both numerator (defense dollars) and denominator (total federal spending). The FY2019 data reflect a period before the COVID-era surge in non-defense mandatory and emergency spending that significantly expanded the denominator and thus reduced defense’s percentage share even as defense outlays were not collapsing in nominal terms ^{[2] [4]}.

2. The pandemic-era fall: why defense’s share dropped to about 11% in 2020–2021

Analysts report a low of about 11% for defense in 2020 and 2021, a decline driven not by a sharp reduction in defense appropriations but by a surge in total federal expenditures tied to pandemic relief, economic stabilization, and mandatory program outlays ^{[3] [5]}. In short, the denominator grew faster than the numerator: emergency stimulus, expanded unemployment benefits, and health spending sharply increased total federal spending, pushing defense’s share down even as defense budgets remained substantial. The data in these sources emphasize the distinction between nominal increases in defense dollars and their percentage relationship to a much larger federal budget during crisis years ^{[3] [5]}.

3. The rebound to 13.3% in 2023 and the concurrent rise in nominal defense spending

By 2023, reports indicate defense accounted for 13.3% of the federal budget with $820.3 billion spent, marking a partial rebound in share alongside a clear increase in nominal defense spending compared with the FY2019 baseline ^[3]. That pattern—higher absolute defense outlays but a lower or only partly recovered share of the total budget—reflects competing fiscal pressures: growing mandatory spending on Social Security, Medicare, Medicaid, and debt service, plus episodic emergency spending. The rebound from 11% to 13.3% therefore represents both recovery from the pandemic-driven denominator spike and actual increases in defense appropriations ^[3].

4. Longer-term trends, growth rates, and future projections that matter

Long-range context in the supplied analyses shows defense has grown in nominal terms over decades (a cited 62% rise since 1980) even as its share of total federal spending has varied; peaks and troughs track wars, economic cycles, and policy choices ^{[3] [4]}. The Congressional Budget Office projections referenced indicate defense-related costs are expected to increase over coming decades, including substantial planned spending on nuclear forces and projected increases in defense outlays between 2029 and 2039, signaling that nominal defense burdens are likely to continue rising even if percentage shares fluctuate ^{[6] [4]}. These projections matter because future shares will depend on both defense budget policy and the trajectory of nondefense mandatory and interest spending.

5. What the available numbers don’t tell you—and why that omission matters

The supplied sources do not consistently break down which components—base DoD budgets, overseas contingency operations, veterans’ benefits, or nuclear modernization—drive the dollar changes, nor do they uniformly present a common denominator (total federal outlays versus total discretionary outlays). Several summaries note that defense is a large portion of discretionary spending but a smaller share of total spending, and some graphics referenced lack explicit year-to-year percentage tables needed for precise trend analysis ^{[7] [8] [4]}. That omission matters because policy debates hinge on whether increases are in procurement, personnel, veterans’ care, or episodic war costs, and percentages alone can obscure where new dollars are actually directed ^{[7] [4]}.