Even as US-Iran peace negotiations edge toward a potential resolution, a growing chorus of Wall Street bond strategists is sounding an uncomfortable warning: long-term Treasury yields may not fall meaningfully — even after the war ends. The message, delivered by analysts at Goldman Sachs, Barclays, ING Bank, and Bank of America, challenges the widely held assumption that a ceasefire and cooling energy prices will automatically bring borrowing costs back down to pre-war levels.
The Core Warning: Structural Forces Have Taken Over
The speculation, underscored by a Bloomberg analysis and highlighted by strategists at ING Bank NV, Goldman Sachs Group Inc. and Barclays Plc, is that the recent jump in some long-term yields will not fully reverse even if the inflation spurred by costlier oil retreats. That risks keeping market borrowing costs elevated around multiyear highs even after the conflict ends, maintaining pressure on governments and economies.
The rise is driven by structural concerns such as high government debt, fiscal deficits, heavy Treasury issuance, and the economic impact of the AI investment boom — not just short-term inflation fears or geopolitical uncertainty. In other words, the Iran war may have accelerated a trend that was already building beneath the surface of global bond markets.
What Barclays and Bank of America Are Saying
"The argument that duration is selling off globally due to inflation fears is hard to square with market pricing of medium- and long-term inflation risk," said Jonathan Hill, head of US inflation strategy at Barclays. "Instead, the interaction between rising debt levels, potentially higher neutral rates, and AI could be driving real rates higher." The so-called neutral rate is the level which neither spurs nor slows the economy — and if it has structurally shifted upward, markets face a fundamentally different interest rate paradigm than the post-2008 era of ultra-low yields.
Bank of America economists Claudio Irigoyen and Antonio Gabriel echoed this view: "In an environment where larger fiscal deficits become a driver of rising debt servicing costs, the long end of the curve becomes more sensitive." Strategists at Barclays, Goldman Sachs, ING, and Bank of America point to rising real yields, expanding fiscal deficits, growing Treasury issuance, and the long-term economic implications of the artificial intelligence investment boom as key factors behind the recent rise in long-duration rates.
Where Yields Have Been During the Iran War
The US-Iran conflict — which began on February 28, 2026 — triggered a pronounced sell-off in Treasuries as energy-driven inflation fears mounted. The yield on the US 10-year Treasury note rose to as high as 4.48% in late March, its highest level since July 2025, as traders remained concerned about the impact of the war on both inflation and economic growth, and markets began pricing in nearly a 50% chance of a Fed rate hike by December — a sharp reversal from earlier expectations of two rate cuts this year.
The benchmark US yield climbed nearly 13 basis points in a single week in mid-March, amid mounting concerns about an energy-driven inflationary spiral and worries over fiscal imbalances linked to war-related spending. While yields have moderated somewhat with the April ceasefire and improving diplomatic signals, they remain well above pre-conflict levels — and strategists say the floor has likely shifted permanently higher.
Bessent's Pushback — and Why Markets Are Skeptical
The White House has offered a more sanguine view. U.S. Treasury Secretary Scott Bessent said he views elevated yields and headline inflation as "transient," subsiding when the conflict ends. Bessent told Reuters in an interview that central bankers at a G7 finance leaders meeting in Paris voiced more concern than he did about inflation and a bond market sell-off. "I think if you're a central banker, you're supposed to say that you're concerned about it," Bessent said. "The tougher you talk, the less you have to do about it."
Markets, however, appear unconvinced. Bond investors are increasingly pricing in a structurally higher rate environment that will outlast any geopolitical resolution — reflecting deep-seated concerns about U.S. fiscal sustainability, the pace of Treasury issuance, and the long-term implications of the AI capital expenditure supercycle on neutral interest rates.
What This Means for Investors
The implications of persistently high yields are far-reaching. For equity markets, elevated discount rates compress valuations — particularly for growth stocks. For governments, higher borrowing costs mean larger interest payments on expanding debt loads. For mortgage borrowers and businesses, the hoped-for relief of lower rates may remain elusive far longer than expected. And for fixed-income investors, the traditional defensive role of long-duration bonds becomes far more complex to execute.
For authoritative data on U.S. Treasury yields, real rates, and bond market trends, the U.S. Department of the Treasury's interest rate resource center provides the most comprehensive official yield curve data available to investors and analysts.
The bottom line from Wall Street's top bond desks is sobering: the Iran war may be ending, but the era of cheap borrowing may not be coming back. Investors who positioned for a rate-cut cycle post-ceasefire should take note — the structural shift in global bond markets may be far more durable than the conflict that temporarily masked it.