The US is adding a trillion dollars to the national debt every 100 days, and it is now passing the size of the Defense Department budget and compounding.

There are two parts. (a) Total US public debt was rising by about $1 trillion every 100 days in the period up to January 2025. (b) 'It' is passing the Defense Department budget and compounding. Read 'it' in (b) as federal interest costs on the debt, since the debt itself is many times the defense budget. Part (a) counts as met if Treasury 'Debt to the Penny' data show roughly $1 trillion added over about 80–120 days in 2024. Part (b) counts as met if federal net interest outlays for FY2024 or the current fiscal year equal or exceed, or are at that moment overtaking, DoD/national defense outlays, and are growing. True: both parts hold. Mostly true: both hold, with a minor slip, e.g. a trillion took about 120–140 days, or interest matched or exceeded defense only on one measure (net vs gross interest, DoD vs national defense). Mixed: one part holds and the other clearly fails. Mostly false: both are directionally right but materially overstated, e.g. a trillion took well over 140 days and interest was still clearly below defense. False: both parts are clearly wrong.

Set before the research began.

1. E1 Final 2024 CS charts - Bureau of the Fiscal Service Bureau of the Fiscal Service (U.S. Treasury)

   “Net Interest outlays were(cid:3)$881.0 billion in fiscal year 2024,(cid:3)an increase of 33.7 percent or(cid:3)$221.8(cid:3)billion above the prior fiscal year.”

2. E2 Final 2024 CS charts - Bureau of the Fiscal Service Bureau of the Fiscal Service (U.S. Treasury)

   “National Defense outlays were(cid:3)$874.0 billion in fiscal year 2024,(cid:3)an increase of 6.5 percent or(cid:3)$53.3(cid:3)billion above the prior fiscal year.”

3. E3 Interest Costs Have Nearly Tripled Since 2020 | Committee for a Responsible Federal Budget Committee for a Responsible Federal Budget · 20 November 2024

   “We spent more on interest on the national debt in FY 2024 than national defense or Medicare.”

4. E4 My weekly column: We must stop our rapid accumulation of debt Rep. Randy Feenstra (congressional office column) · 27 November 2024

   “At the end of July, our national debt peaked at $35 trillion – a figure once considered unthinkable. However, just 118 days later, our country surpassed another sobering milestone – $36 trillion in debt.”

5. E5 US national debt hits a new record: $36 trillion Fox Business · 4 November 2024

   “The $36 trillion debt milestone comes just months after the U.S. eclipsed the $35 trillion mark in late July 2024. The national debt has passed other trillion-dollar milestones in the past year, as the $34 trillion mark was reached in early January 2024”

6. E6 US national debt hits a new record: $36 trillion Fox Business · 4 November 2024

   “Spending on net interest payments on the debt rose by $240 billion in fiscal year 2024 compared with the prior year and exceeded spending on defense and Medicare.”

7. E7 What to Know About Interest Spending and Crowd Out Third Way · 11 December 2025

   “Interest is currently the third-largest budget item ($881 billion in FY 2024, $970 billion in FY 2025), larger than Medicaid ($618 billion in FY 2024, $688 billion in FY 2025) and defense ($874 billion in FY 2024, $917 billion in FY 2025).”

Part (b) holds. Treasury figures show FY2024 net interest outlays of $881.0B, up 33.7%, against national defense outlays of $874.0B (E1, E2), and CRFB, Fox Business and Third Way all report that interest exceeded defense (E3, E6, E7). Part (a) holds for the most recent step: the debt went from $35T at the end of July 2024 to $36T in about 118 days (E4, E5). However, the earlier step from $34T in early January to $35T in late July took roughly 200 days (E5). Across 2024 the pace averaged slower than $1T every 100 days, so this is a minor slip rather than a failure of part (a).