KEY POINTS
- Dow futures fell 256 points, S&P 500 futures lost 0.55%, and Nasdaq futures shed 0.6% after Trump announced a naval blockade of the Strait of Hormuz effective 10 a.m. ET Monday.
- The blockade follows the collapse of weekend peace talks between the U.S. and Iran, escalating a conflict that has already driven oil prices up nearly 50% since late February.
- Traders should watch the 6,750 level on the S&P 500 as the next line of technical support, with Tuesday's PPI release likely to amplify volatility.
U.S. stock futures fell sharply early Monday after President Donald Trump ordered a full naval blockade of the Strait of Hormuz, the 21-mile-wide chokepoint through which roughly 20 million barrels of oil pass every day. Dow futures dropped 256 points, or 0.5%. S&P 500 futures lost 0.55%. Nasdaq 100 futures shed 0.6%. The move came hours after Vice President JD Vance confirmed that weekend peace negotiations between Washington and Tehran had ended without a deal.
The blockade, which U.S. Central Command says takes effect at 10 a.m. ET Monday, threatens to choke off roughly a fifth of the world's seaborne oil trade at a moment when energy markets are already under severe strain. Brent crude jumped 7.5% to above $102 a barrel overnight. West Texas Intermediate soared 8% to above $104. The dollar rose 0.2%, its biggest gain in more than a week, as traders fled to safety.
A Strait the World Cannot Afford to Lose
The Strait of Hormuz connects the Persian Gulf to the Gulf of Oman and the open ocean beyond. It is the single most important oil transit chokepoint on Earth. Saudi Arabia, Iraq, the UAE, Kuwait, and Qatar all depend on it to move crude to global markets. When Trump posted on Truth Social late Sunday that the U.S. would block "any and all Ships trying to enter, or leave" the strait, he effectively declared economic war on Iran's remaining export capacity while simultaneously threatening the flow of allied oil.
Iran's Islamic Revolutionary Guard Corps responded within hours. A statement carried by the semi-official Fars News agency warned that any military vessels approaching the strait "will be dealt with harshly and decisively." That rhetoric echoes similar warnings Iran issued in March, but the presence of a U.S. carrier strike group in the region gives both sides less room to bluff.
Oil prices have now surged nearly 50% since February 28, the day U.S. military operations against Iran began. Brent traded near $60 in late February. It cracked $100 for the first time during this conflict last week. The latest blockade announcement sends it deeper into triple digits, and the trajectory suggests further upside unless diplomacy resurfaces. The national average for a gallon of gasoline stood at $4.12 on Sunday, up 38% since the war began.
Winners, Losers, and the Earnings Gauntlet
The sectoral math is straightforward. Energy is the clear winner in 2026, with the Energy Select Sector SPDR Fund returning 18% year to date as earnings estimates for major producers get revised sharply higher. Defense stocks continue to benefit as well. Lockheed Martin is up nearly 30% on the year. RTX has climbed on the back of Tomahawk missile demand, with reports indicating the U.S. has fired more than 850 Tomahawks since operations began.
Airlines sit on the other side of the ledger. Jet fuel prices have nearly doubled since late February, from $2.50 per gallon to $4.88. Delta, United, and American have all revised 2026 earnings guidance downward. Southwest Airlines dropped more than 20% in the past month alone. Carriers are cutting capacity plans for the second quarter, and UBS expects more reductions in the coming weeks.
Monday also marks the start of a heavy earnings week. Goldman Sachs reports before the bell, with analysts expecting revenue of $16.9 billion and EPS around $16.41, driven by an 18% jump in its Global Banking & Markets division. Fastenal and Children's Place also report. But the macro backdrop will dominate. With the Hormuz blockade taking effect during market hours, expect energy names to gap higher at the open and airlines to test new lows.
What Comes Next
The S&P 500 closed Friday at 6,816.89, down roughly 4% on the year. The index has absorbed a war, a 50% oil spike, and a hot CPI print in the span of six weeks, and it has not yet broken below its March lows. That resilience will be tested this week. Tuesday brings the March PPI report, which will tell traders whether wholesale prices are confirming the energy-driven inflation surge that showed up in last Thursday's CPI. Fed speakers are scheduled every day this week. And the Hormuz blockade introduces a genuine tail risk: if Iran retaliates against commercial shipping, oil could push well past $110, and the inflation math for the second half of 2026 changes dramatically. Watch 6,750 on the S&P 500 as the next level of meaningful support.
