The US government’s interest costs are climbing sharply as the national debt reaches $40 trillion, economists warned this week, casting doubt on White House projections that faster growth can shrink the burden.
Interest payments on the debt now rank among the largest lines in the federal budget, rivaling defense and major entitlement programs. “The interest payments are starting to snowball,” said Joe Boyle of Hartford Funds, pointing to the compounding effect of higher yields on a rising stock of borrowing.
The math is unforgiving. As older, low-rate debt matures and is refinanced at current yields, the average interest rate the Treasury pays on its obligations continues to rise. Each increase feeds directly into future deficits, which in turn require more borrowing.
President Donald Trump has argued that stronger economic expansion can outrun the debt, framing the strategy as a path back to fiscal health. Budget analysts describe the pitch as appealing but detached from arithmetic. Growing out of a $40 trillion obligation would demand sustained growth rates far above what the US economy has delivered in recent decades.
The debt has doubled over the past 10 years, driven by pandemic spending, tax cuts and rising outlays. Higher benchmark yields have made servicing that total steadily more expensive, leaving less room for other priorities.
The Treasury has taken steps to manage the pressure, including expanded bond buybacks aimed at improving market functioning and smoothing its borrowing profile. Those measures address liquidity rather than the underlying trajectory of the debt itself.
Economists note that closing the gap through growth alone would require productivity gains and labor expansion on a scale rarely seen outside wartime or postwar booms. Absent that, the alternatives narrow to higher taxes, spending cuts or continued borrowing at elevated rates.
Investors are watching the coming rounds of Treasury auctions for signs of how much demand exists for the growing supply of government debt. Yield movements at those sales will shape the interest bill the government faces in the years ahead.