Markets Climb a Blockade: S&P 500 Hits Record as US Vows 'Indefinite' Iran Siege

Six months into the US-Iran war, Washington has stopped talking about when it ends. Defense Secretary Pete Hegseth told reporters on August 14 that the US Navy can maintain its blockade of Iranian ports “indefinitely,” rotating warships in and out of the region as needed.^[1] Wall Street heard that and bought stocks anyway: the S&P 500 closed at a record 7,798.99, after notching an all-time intraday high above 7,800, on track for its third straight weekly advance.^[1]

The juxtaposition is stark. Brent crude settled at $87.07 on Thursday and climbed above $88 a barrel on Friday, gaining more than 5% for the week.^[1][2] Treasury Secretary Scott Bessent said Washington would impose further economic pressure on Iran to reopen the Strait of Hormuz, while President Trump told Americans to accept higher gasoline prices as the cost of restraining Tehran.^[2][3] Iran, for its part, called on the US to lift the blockade and remained defiant on the strait, with no sign of active peace talks.^[3] Oil is now inching toward $90 on continued tanker attacks and the absence of diplomatic progress.^[2]

The question worth asking is not why stocks are rising — earnings have been strong, July CPI landed in line at 3.4%, and AI infrastructure spending continues to accelerate^[4] — but whether the market is pricing geopolitical resilience or simply failing to price geopolitical risk.

The Chokepoint Economy

The Strait of Hormuz has been effectively choked for roughly five months. Supertankers carrying even non-Iranian crude have taken to going dark — switching off transponders for extended periods to transit Hormuz and the Bab el-Mandeb strait, doubling down on evasion tactics honed in the early days of the conflict.^[5] What began as brief blackouts of a few hours has become a routine, longer-duration practice.

The cost of moving oil through these contested waters has exploded. Supertanker rates on the benchmark Middle East-to-China route have neared $500,000 per day, more than double the $200,000 daily rate that prevailed before the Iran war began.^[3] That cost does not simply vanish into the freight market; it is absorbed into landed crude prices, feeding through to refinery margins and, ultimately, consumer fuel costs.

Saudi Arabia’s Pipeline Pivot

Saudi Arabia is rerouting its oil exports on a scale that suggests a structural shift, not a temporary workaround. Exports from Egypt’s Mediterranean port of Sidi Kerir — fed by the Sumed pipeline from the Red Sea — more than doubled to approximately 2.3 million barrels per day in August, up from roughly 1 million bpd in July.^[6]

The trigger was the Houthi declaration of a maritime embargo against the kingdom. Saudi exports from the Red Sea port of Yanbu through the Bab el-Mandeb Strait collapsed by nearly 90% to 1.3 million barrels for the week of August 3, compared with 11 million barrels for the week of July 20, when the Houthis announced the embargo.^[6] Saudi Aramco CEO Amin Nasser confirmed on the company’s August 4 earnings call that Riyadh has “optionality” through multiple access routes and alternative pathways to the Mediterranean.^[6]

But the reroute is expensive. Tankers must take a journey roughly 25 days longer around Africa to reach the Asian customers Saudi Arabia typically supplies.^[6] Most Sidi Kerir exports are now heading to the US and Europe rather than Asia — a sign that the longer voyage is not cost-effective for Asian buyers, triggering what Kpler’s Matt Smith described as a “domino effect” reshaping global crude trade flows.^[6]

The Second Front: US-China Sanctions

Even as the Iran conflict dominates headlines, a second geopolitical pressure point is building. Weeks ahead of a planned state visit by Chinese President Xi Jinping to the United States, Beijing and Washington have revived a tit-for-tat exchange of sanctions.^[7]

China announced its broadest package of trade countermeasures since last October’s Busan truce, including controls on drone exports to the US and a ban on dealings with six American entities.^[7] The measures were retaliation for recent US restrictions, and analysts at BNP Paribas noted that China appears to be replicating Washington’s playbook — curbing the flow of Chinese technology to the US rather than merely responding with tariffs.^[7]

The timing is delicate. Xi’s expected visit to Washington next month could either stabilize the relationship or become a flashpoint if either side perceives the other’s sanctions as a breach of the truce.^[7] For markets, the US-China sanctions flare-up is a quieter risk than Hormuz — it does not move oil prices overnight — but it carries structural implications for technology supply chains, semiconductor trade, and the AI hardware buildout that has been a primary engine of the equity rally.

What the Market Is Pricing

The S&P 500’s record close alongside $88 oil and an “indefinite” blockade is not irrational if one assumes the following: that corporate earnings will continue to absorb higher energy costs, that AI capital expenditure will remain insensitive to geopolitical risk, and that the Federal Reserve will keep inflation contained despite oil’s persistent pressure. July CPI of 3.4% was in line with expectations, and softer PPI, retail sales, and sentiment readings reduced near-term odds of a Fed rate increase below 30%.^[4] That gave the front end of the Treasury curve room to rally, even as long-dated yields stayed pressured by issuance.^[4]

The United Kingdom illustrates the other side of the trade. UK GDP expanded 0.4% in Q2 after 0.6% in Q1, putting it on track to be the G7’s fastest-growing economy for a second straight quarter.^[1] But the IMF warned in April that the Iran war would damage Britain’s growth more than any other rich country’s, because the UK imports a large share of its oil and gas, and pump prices are already eating into household incomes.^[1] The growth and the vulnerability coexist — which is precisely the condition the US market may be in, with the difference that the US has not yet felt the consumer-side squeeze to the same degree.

What to Watch Next

• Hormuz negotiation status. Any confirmed breakthrough on reopening the strait would likely trigger sharp oil selling — Energy Aspects notes that “peace headlines trigger aggressive selling” in crude markets, even as supply disruptions of comparable significance draw muted responses.^[8] The absence of progress is what has been driving prices toward $90.

• Xi’s Washington visit. Whether the US-China sanctions exchange escalates or de-escalates before the summit will shape technology supply-chain expectations. A breakdown would put AI hardware names — the rally’s primary engine — directly in the crossfire.

• Consumer-level oil pass-through. Thus far, the equity market has treated higher oil as a corporate margin issue rather than a demand-killer. If gasoline prices begin to materially compress US consumer spending — the UK’s IMF-flagged vulnerability is the template — the “wall of worry” narrative gets harder to sustain.

• Saudi rerouting permanence. If Sidi Kerir flows remain elevated into September, the structural reshaping of global crude routes is effectively confirmed, and the cost premium of longer voyages becomes a permanent feature of landed oil prices rather than a temporary dislocation.

FN2 Research provides financial research and education, not personalized investment advice. This article does not constitute a recommendation to buy, sell, or hold any security.