Hormuz Blockade Goes Indefinite as Brent Clears $88; Senate Hands Trump a 100% Tariff Hammer

Two geopolitical risk vectors that markets have been pricing separately are now hardening simultaneously — and the week ahead may force them into a single trade.

The first is the Strait of Hormuz. Defense Secretary Pete Hegseth told reporters on August 13 that the US Navy can maintain its blockade of Iranian ports “indefinitely” by rotating ships in and out, as it has been doing since the Iran war began in February^[1]. Treasury Secretary Scott Bessent separately promised “measures like have never been seen in the history of economic isolation on a country,” with more announcements expected this week^[1]. The comments killed any remaining market hope for a near-term diplomatic off-ramp.

The second is the sanctions superstructure taking shape in Washington. On August 7, the Senate voted 86–11 to pass the Lindsey O. Graham Sanctioning Russia and Iran Act of 2026, which authorizes the president to impose tariffs as high as 100% on the top five importers of Russian oil and gas^[2]. The House will not vote until September due to summer recess, but the bill’s tariff authority — which could reach China, India, the EU, Japan, and South Korea — gives the executive branch what Cato Institute scholars called “unchecked authority” to set rates “at the president’s whim”^[2].

These two threads are converging at the worst possible moment for inflation.

Hormuz: traffic collapse, supply drain

The numbers tell the story. Shipping through the Strait of Hormuz fell to just 8 vessels on August 12, compared with a pre-war average of 130 to 140 ships daily^[1]. The strait carried roughly one-fifth of the world’s oil and liquefied natural gas before the conflict^[1].

The International Energy Agency on August 12 revised its forecast: global oil supply will fall by 4.3 million barrels per day this year — about 4% — up from the 3.7 million bpd drop projected just a month earlier^[1]. The US Energy Information Administration followed with its own revised outlook, forecasting Brent crude to average $85 per barrel in Q3 2026 and warning that Middle East production will not return to near pre-conflict levels until early 2027^[3].

Brent futures closed Friday at $88.52 per barrel, up 1.7% on the day and more than 5% for the week^[4]. WTI settled at $82.40^[4]. Brent is now up roughly 24% from before the war began in late February^[3].

Iran is not passively blockaded — it is actively striking shipping. The UAE reported that Iran attacked two vessels from the state-owned Abu Dhabi National Oil Company transiting the strait on August 14^[1]. Separately, Yemen’s Iran-backed Houthis killed six people in a missile attack on a commercial vessel in the Bab el-Mandeb strait^[3]. US Central Command disabled a Panama-flagged cargo vessel that attempted to break the blockade of Iranian ports^[3].

Tanker tracking firms report that supertankers are going dark — turning off transponders for longer stretches — to move oil through Hormuz and Bab el-Mandeb, doubling down on tactics from earlier in the Iran war^[5]. Bloomberg reported the trend on August 14.

The market reaction in equities was measured but directional. As of the August 14 close, ExxonMobil (XOM) finished at $160.09, up 0.93%^[6]. Chevron (CVX) closed at $200.01, up 1.17%^[6]. ConocoPhillips (COP) ended at $126.78, up 1.81%^[6]. The United States Oil Fund (USO) rose 1.26% to $126.60^[6], while the Brent ETF (BNO) gained 1.81% to $50.64^[6]. Gold (GLD) drifted higher by 0.63% to $401.48^[6], and the long bond ETF (TLT) fell 0.67% to $82.04^[6] — a mild risk-off tilt that stopped well short of a flight to safety.

China: the truce frays from both sides

While Hormuz dominates the energy narrative, the US-China trade relationship is deteriorating in parallel — and the Russia sanctions bill could accelerate that erosion.

On August 5, Beijing announced its broadest package of trade countermeasures since last October’s Busan truce^[7]. China’s Ministry of Commerce barred Chinese entities from doing business with seven American companies and organizations, tightened export controls on US-bound drones and related technology, and prohibited Chinese firms from cooperating with US compliance and certification bodies — including mandatory factory inspections^[7]. Six of the named entities were sanctioned over Xinjiang-related measures, marking the first time Beijing has retaliated against firms enforcing the Uyghur Forced Labor Prevention Act^[7].

Eurasia Group assessed that Beijing is raising enforcement costs for American firms while keeping the measures reversible ahead of bilateral talks^[7]. BNP Paribas analyst William Bratton noted that China is “starting to replicate” Washington’s playbook — constraining the flow of Chinese products and technologies to the US rather than merely protesting restrictions on Chinese access^[7].

The next day, August 6, Trump signed executive orders targeting Chinese dominance in polysilicon (solar) and chips, framing the measures as competition policy^[8].

Then on August 13, the White House published a report accusing more than 40 countries of helping China dodge US tariffs through transshipment — routing goods through third countries for packaging and limited assembly^[9]. White House trade adviser Peter Navarro described the practice as the “great transshipment scam” that has let China “launder its exports,” with estimated annual tax revenue losses of $19 billion to $26 billion^[9]. US Customs and Border Protection has begun an AI-powered prototype program to detect falsified origins, with retroactive tariffing going back roughly one year^[9].

The timing is deliberate. Xi Jinping is expected in Washington in September, following Trump’s May visit to Beijing^[7]. Both sides are generating leverage — but the Graham bill’s tariff authority means the leverage is asymmetric. If Trump invokes 100% tariffs on China as a “top buyer of Russian energy,” the fragile Busan truce collapses^[2]. Eurasia Group warned that more aggressive steps — restricting Chinese open-weight AI models or curbing chip access through cloud services — would put the truce at risk^[7].

The inflation collision

Here is where the two vectors intersect. July core CPI cooled to 2.5% year-over-year — the lowest since March 2021^[10]. But July PPI rose 4.4%^[10], and the Fed’s FOMC minutes from July 28–29 are due Wednesday, offering a window into how officials assessed inflation before the latest CPI print^[10].

The EIA’s forecast that Brent averages $85 in Q3^[3] — while the spot price is already at $88.52^[4] — suggests the energy pass-through to consumer prices is still building, not peaking. Global economists have forecast a sharp drop in global growth, with potential recession in some regions if the war is not ended soon^[1]. The Russian Embassy in Washington warned of an “impending energy crisis and rising gas prices on the eve of the midterm elections,” calling further sanctions “extremely counterproductive for the United States”^[11].

The base case is that both sides in each conflict are building leverage for negotiations — the Iran blockade to force Tehran back to talks, the China retaliation and Russia bill to strengthen the US hand before Xi’s September visit. If that reading is right, the risk premium in oil and the flight to safety in gold and bonds should remain elevated but contained. The TLT’s modest 0.67% decline on Friday^[6] — rather than a rally — suggests markets are not yet pricing a systemic shock.

But what would have to be true for the risk case to dominate? Three things, any one of which would mark a regime shift:

1. Hormuz stays at 8–12 vessels indefinitely. If the IEA’s 4.3 million bpd supply cut holds into Q4, the oil cushion that absorbed the initial war shock will be exhausted. Global stockpiles are already shrinking^[12]. At that point, $90 Brent becomes a floor, not a ceiling.

2. Trump invokes the Graham bill’s 100% tariff authority. If the House passes the bill in September and Trump immediately targets China or India, the trade truce ends. The Congressional Budget Office has not scored the inflation impact, but tariffs at that level on major trading partners would feed directly into import prices.

3. The Houthis widen the Bab el-Mandeb disruption. A second chokepoint closing — even partially — compounds the Hormuz shortfall and extends the shipping insurance premium across every route connecting Asia to Europe.

What to watch next

• FOMC minutes (Wednesday, August 19): The July 28–29 minutes were taken before the latest CPI and PPI data. Look for language on energy prices and supply chain disruptions — any mention of geopolitical risk in the inflation outlook signals the Fed is tracking the Hormuz situation, not just domestic demand.

• Treasury sanctions announcements: Bessent promised “more announcements coming next week”^[1]. Any escalation beyond the current naval blockade — secondary sanctions on Iranian oil buyers, for instance — tightens the supply vise further.

• Oman-Iran talks on Hormuz: Qatar’s Foreign Ministry said Oman-Iran discussions are at “an advanced stage”^[3], but Tehran insists the strait is separate from broader negotiations and will remain closed until the US lifts sanctions and releases frozen assets^[3]. A breakthrough would remove the oil premium quickly; a breakdown confirms the indefinite blockade posture.

• House vote timing on the Graham bill: Congressional summer recess means no House vote until early September^[11]. If House Democrats’ reservations about the tariff authority harden into opposition, the bill could stall — removing one escalation vector.

• Xi’s September visit to Washington: The trip remains on track^[7], but the Graham bill’s 100% tariff authority and the transshipment crackdown give Trump tools to pressure Beijing during the summit. Whether Xi accepts the invitation — or uses a postponement as leverage — will signal whether the Busan truce survives the year.

The quiet indicator to watch is not the oil price. It is the bond market. TLT’s 0.67% decline on Friday^[6] — a yield rise, not a flight to safety — suggests the market is pricing the energy shock as inflationary rather than deflationary. If that holds, the Fed’s pause becomes a trap, and the geopolitical risk premium migrates from commodity markets into the rate complex. That is the chain reaction worth monitoring.