US Debt Outlook Darkens as Treasury Yields Surge

Soaring Treasury yields are raising significant concerns in Congress, as their precipitous rise in recent months has further darkened the outlook for U.S. debt. The 10-year Treasury yield surged to 5.23% on Friday, marking its highest level since 2007 and representing an increase of more than a full percentage point since just before the Iran war began. Concurrently, the 30-year Treasury yield reached 5.49%, the highest point observed since 2004. These elevated yields are occurring amidst a confluence of factors, including rising oil prices due to the Middle East conflict, substantial annual spending by AI hyperscalers in the hundreds of billions of dollars, and an economy that is described as running "hot." The U.S. national debt has now surpassed $40 trillion, and Treasury yields have already significantly exceeded the long-term projections provided by the Congressional Budget Office (CBO). In its most recent forecasts, issued in February, the CBO had projected the 10-year yield to be 4.1% in the current year, 4.2% in 2027, 4.3% from 2028 to 2031, and 4.4% from 2032 to 2036. These previous projections now appear notably understated given the current market conditions. Treasury yields play a critical role in determining borrowing costs across the economy and dictate the amount the Treasury Department must pay in interest on the national debt. As interest rates rise, these interest expenses accelerate. Annual interest payments on the U.S. debt have already reached $1 trillion, and the budget deficit is on track to hit $2 trillion this fiscal year. There is currently no discernible political will to implement measures to reduce these deficits. The abrupt increase in yields prompted Senator Jeff Merkley, the ranking Democrat on the Senate Budget Committee, to request updated projections from the CBO. In a letter responding to the senator, CBO Director Phillip Swagel outlined a scenario where interest rates were elevated by 1 percentage point above the baseline forecast. This analysis indicated that, even before accounting for broader macroeconomic effects, the primary deficit (which excludes net interest outlays) would be 0.4 percentage points larger by 2056 compared to the baseline view. However, the total deficit would be substantially larger, increasing by 4.9 percentage points, underscoring the significant additional burden that interest expenses will impose. Furthermore, under this higher-interest-rate scenario, the total deficit would balloon to 14% of the Gross Domestic Product (GDP), a stark contrast to the 5.8% expected for the current fiscal year and the historical average of 3.8% observed from 1976 to 2025. This widening gap highlights the fiscal challenges posed by sustained high interest rates on the U.S. national debt.