Markets Wobble as US-Iran Ceasefire Collapses Into Fresh Strikes

A Fragile Peace Unravels

A ceasefire that once seemed to be inching toward a permanent deal has shattered. On July 8, President Donald Trump declared the Memorandum of Understanding with Tehran effectively over, and the United States has since launched waves of airstrikes against Iran — rattling global markets, spiking oil prices, and raising urgent questions about what comes next for a region that had barely caught its breath.

The U.S. military said it had begun a "series of powerful strikes" against Iran after three commercial vessels transiting the Strait of Hormuz came under attack. U.S. Central Command called Iran's aggression "unwarranted, dangerous, and a clear violation of the ceasefire." What had been a tense but functioning truce collapsed almost overnight.

Trump Pulls Back From the Negotiating Table

The Dow Jones Industrial Average fell sharply after President Trump told the NATO summit in Turkey that the ceasefire with Iran was "over" amid renewed hostilities in the Middle East that sent oil prices surging. The S&P 500 fell 0.65%, the Dow Jones Industrial Average lost 1.14%, and the Nasdaq gave up 0.50%. It was a swift and punishing market reaction to words from a single press conference.

Trump had hinted at more strikes at NATO, declaring that "as far as I'm concerned, it's over," and also said he's not sure he wants to make a deal with the Iranians, calling Iran's leaders "sick" and declaring it "a waste of time dealing with them." This came after Trump said on July 8 he may no longer be interested in negotiating a deal with Iran, and declared the ceasefire between the U.S. and Tehran "over" following another wave of attacks in the Middle East.

The U.S. military said it struck around 90 targets across Iran after Trump declared the fragile ceasefire over following Iranian attacks on shipping in the Strait of Hormuz. Iran launched more missiles at U.S. allies and said at least 14 people were killed in U.S. airstrikes over the past two days as the conflict between Washington and Tehran escalated.

Oil Surges, Inflation Fears Return

International Brent crude futures settled up 5.43% at $78.19 per barrel, while West Texas Intermediate futures popped 4.37% to close at $73.52. Energy stocks surged in response, while technology shares took a hit as investors rotated out of growth plays and into more defensive positions.

The International Monetary Fund modestly downgraded its outlook for the global economy, citing the energy shock caused by the Iran war, though the fallout is being partially offset by booming investment in artificial intelligence and other technologies. The IMF now expects the global economy to expand 3% in 2026, down from 3.5% in 2025. The Federal Reserve's minutes from its June meeting confirmed that several members of the Open Market Committee favored raising rates at that meeting in light of rising inflation caused by the Iran war's impact on energy prices. That combination — slowing growth and rising prices — is exactly the kind of stagflationary environment that keeps investors up at night.

A Slim Opening Remains

U.S. stocks rose on Thursday, July 9, as investors focused on AI prospects, setting aside jitters over a flare-up in U.S.-Iran hostilities. The market's resilience suggests traders aren't fully pricing in a prolonged conflict — yet. But the situation remains deeply unstable.

Crude futures pulled back after President Trump said Iran called to make a deal, and mediators from Qatar and Pakistan are also working to bring the two sides to the negotiating table. As Megan Horneman, chief investment officer at Verdence, put it: "It's highly inflationary and highly uncertain. It could end tomorrow. It could turn into a bigger event. We don't know that." With diplomatic back-channels still open and both sides having demonstrated their willingness to escalate, the next 72 hours may prove decisive — for the Middle East, for global energy markets, and for the economic outlook heading into the second half of 2026.