Treasury Yields Spike as Iran War Drives Bond Market Selloff

The 10-year U.S. Treasury yield is sitting at 4.44%, up from 3.95% before the Iran war kicked off at the end of February, according to the Associated Press. That's a 49-basis-point jump in roughly three months.

At the peak in mid-May, the rate touched 4.67%. It has since eased slightly as Iran ceasefire negotiations progressed.

The Energy Shock and Bond Markets

The energy price spike from the Iran conflict moved beyond gas stations and into bond markets. Higher energy costs mean higher expected inflation. Higher expected inflation means bond investors demand higher yields to compensate. Higher yields mean the U.S. government — already carrying $1.8 trillion in annual deficits — pays more to borrow.

Kent Smetters, faculty director of the Penn Wharton Budget Model, attributed 60% of the Treasury yield increase to inflation expectations driven by the energy shock, according to AP reporting.

The Cost to Households

Mortgage rates have climbed to their highest levels in nine months, according to AP. Auto sales are slumping.

Homebuyers and car buyers are already feeling the impact in real monthly payments. If you were waiting to buy a house this spring, you're paying more — a direct result of government debt and the energy shock from war.

Trump's Deficit Proposals

Trump has pointed to multiple strategies to address the deficit: tariff revenue, "Gold Card" visa fees from foreign nationals, DOGE spending cuts, and faster economic growth. Last week, Trump said the fraud task force led by Vice President JD Vance would unlock "massive savings," adding that "if he does really great, we'll have a balanced budget without having to do anything."

Jessica Riedl, a senior fellow at the Manhattan Institute, was skeptical. "President Trump signed a tax cut bill that will likely add $5 trillion to 10-year deficits — and tariffs are offsetting only a small fraction of those costs," she told AP. "Budget deficits are still projected to soar past $4 trillion annually within a decade under current policies."

Riedl also noted that the cost of servicing the national debt has tripled since 2021 to more than $1 trillion annually. That's interest alone, every year.

This isn't a problem created by one administration. Social Security and Medicare costs are mathematically guaranteed to outstrip tax revenues over the next decade — a structural issue neither party has addressed. Democrats spent the last decade refusing entitlement reform. Republicans are now proposing tax cuts while the debt spirals. Both represent real fiscal problems.

A Global Confidence Crisis

Interest rates have risen for multiple countries simultaneously, according to AP. The world is repricing sovereign debt risk everywhere — driven by post-war inflation fears, AI investment demand for capital, and growing recognition that most Western governments carry unsustainable debt loads.

Gold's 42% rally in 2025 was an early signal. The bond market is now following suit.

When global investors start demanding higher rates from multiple governments at once, that signals a confidence crisis. Confidence, once lost, is difficult to restore.

The Current Situation

Treasury yields at 4.44%, mortgage rates at a 9-month high, auto sales slumping, and the Iran war still ongoing — this is what sovereign debt stress looks like when it moves from theoretical to real, hitting monthly household bills.

Trump's deficit math doesn't resolve the structural problem. Neither did Democratic spending in prior years. And the bond market — indifferent to party affiliation — is charging America a premium for decades of fiscal choices from both sides.