Black Sea Shipping Crisis Compounded by Iran War Costs Pushes Treasury Yields to Multi-Year Highs
Claire Weston
The 10-year Treasury yield broke 4.7% and the 30-year hit 5.18% — the highest since before the 2007 financial crisis — as $100 oil and ballooning Iran war costs force the bond market to reprice geopolitical risk.
How far have yields climbed?
The 10-year U.S. Treasury yield broke through 4.7% on Thursday, its highest since January 2025.
The 30-year yield rose to 5.18% — last seen before the 2007 financial crisis.
This means → the market's anxiety about long-run inflation and fiscal risk is back at pre-subprime-crisis levels.
What happened in the Black Sea — and why does it push oil higher?
Russia's defense ministry warned this week that all vessels in its Black Sea exclusive economic zone face safety risks.
Ukraine's military said it struck at least 124 Russia-linked vessels between July 8 and 20, including 89 oil tankers — Bloomberg noted it could not independently verify the figures.
A Saudi tanker was also hit; combined with mutual U.S.–Iran threats, Brent crude briefly topped $100 a barrel on Thursday.
In plain terms = when shipping lanes in oil-producing regions are unsafe, oil can't get out, prices rise, inflation expectations follow — and bond yields get dragged up with them.
How direct is the oil-to-yield link?
B. Riley chief market strategist Art Hogan was blunt: "Yields aren't coming down unless oil comes down." He defines anything above 4.5% as the bond market's "danger zone."
Brean Capital head of fixed-income strategy Scott Buchta agreed: "It's oil. Period."
Buchta started the year forecasting the 10-year at 4.5%–4.6% by year-end, but said if the conflict persists, that range shifts to 4.6%–4.8%.
This means → whether oil can retreat from $100 is the single most important variable for judging if yields have peaked or keep climbing.
How big is the Iran war bill?
Defense Secretary Pete Hegseth told a Senate hearing the Iran war has cost roughly $37.5 billion so far.
The Pentagon is seeking another $67 billion in supplemental funding — together exceeding $100 billion.
This reflects a second channel through which geopolitical conflict lifts yields: government borrows more → issues more Treasuries → bond supply rises → yields climb.
What is the damage to equities?
The S&P 500 fell about 1% on Thursday, the Dow dropped more than 500 points, and the Nasdaq 100 slid 1.4%.
JPMorgan's market-intelligence team wrote: "The worry is that yields are approaching the tipping point that forces an equity correction."
In plain terms = the higher bond yields go, the greater the opportunity cost of holding stocks. Once yields cross a psychological threshold, capital migrates from equities to bonds.
What to watch next?
JPMorgan framed it as "a race to see whether Trump pivots" — a policy de-escalation signal could cap yields.
Hogan noted the deficit problem "isn't new, but it keeps getting worse," and argued inflation remains the primary driver of the yield move.
This means → two observation windows matter most in the near term: whether oil falls back below $100, and whether the conflict produces a diplomatic off-ramp. Until one of those breaks, the bond market's "war premium" has no reason to unwind.
Content is for reference only, not financial advice.