Post #72 traced the escort gap — how CENTCOM's triage left product tankers unprotected while prioritizing crude VLCCs. That gap lands hardest at one specific point in the chain: the steam cracker. And what happens at the cracker depends entirely on what it eats.
The fork
A steam cracker breaks hydrocarbon feedstock into ethylene, propylene, and other building blocks of plastic. But there are two fundamentally different feedstocks, and Hormuz only blocks one of them.
Naphtha comes from crude oil refining. In Asia, 54% of naphtha supply and 45% of LPG supply transited Hormuz in 2025. When the strait filtered shut, the feedstock disappeared.
Ethane comes from natural gas processing. In North America, shale gas provides virtually unlimited ethane. Hormuz is irrelevant.
Same crisis. Same day count. Completely different outcomes.
Asia: the damage zone
Northeast Asian cracker utilization collapsed from 83% in February to 57% by May — the worst on record. In South Korea, YNCC declared force majeure on both its crackers (915k and 900k tonnes/year). In Indonesia, Chandra Asri did the same. In Taiwan, CPC Corp cut to minimum rates. JPMorgan estimates 5% of global ethylene capacity has shut in Japan, South Korea, and China combined.
The economics are brutal. Spot production cash margins for naphtha crackers in Northeast Asia hit -$303/MT in the week ending July 9. That's not thin margins — that's losing money on every tonne produced. BOPP film converters downstream have been operating at negative spreads since July 10: the price of finished film below the cost of the resin input.
By August, Chinese feedstock inventories were projected to last only through end of month. Japan: three weeks of coverage. Some flexible crackers are switching to LPG — cheaper, regionally available — but LPG cracking yields less ethylene per tonne and requires different catalyst configurations. It's a survival measure, not a solution.
North America: the island
US polyethylene production hit 5.91 billion pounds in March 2026 — an all-time record. Operating rates: 90-98%. US linear PE exports set their own record in March, with new trade flows opening to Europe, Turkey, and Latin America.
The reason is geological. North American crackers run on ethane from Marcellus, Permian, and Haynesville shale gas. Natural gas prices barely moved while crude doubled. The feedstock cost advantage was already structural; Hormuz made it absolute.
LyondellBasell's CFO said it plainly: there is now an "opportunity to even start exporting out of North." That sentence describes a trade flow reversal that didn't exist 190 days ago.
Europe: the exit
European naphtha crackers were already uncompetitive before Hormuz — energy costs 3-4x US levels, carbon pricing, aging infrastructure. The crisis is accelerating what was already underway.
Seven crackers closing by 2027:
| Company | Site | Capacity (kt/yr) | Status |
|---|---|---|---|
| Dow | Böhlen, Germany | 510 | Closing Q4 2027 |
| TotalEnergies | Antwerp, Belgium | 580 | Closing 2027 |
| LyondellBasell | Berre, France | 400 | For sale |
| LyondellBasell | Münchsmünster, Germany | 465 | For sale |
This isn't cyclical. These crackers aren't idling to wait for feedstock prices to normalize. They're closing permanently or being divested. Hormuz didn't cause the European petrochemical exit — but it removed the last argument for staying.
China: the arbitrage
China is the anomaly. It's a naphtha-dependent economy that should be crushed alongside South Korea and Japan. Instead:
- PVC exports: +86.7% YoY in March. 684,000 tonnes. Q1 cumulative: 1.42M tonnes (+45% YoY).
- PE exports: +479% YoY in April. 550,000 tonnes in a single month.
- PP exports: projected to reach 5 million tonnes in 2026.
- Hengli Petrochemical: Q1 profit +90.65%.
- Wanhua Chemical: Q1 profit +20.6%.
The mechanism is the IRGC filter mapped in Posts #70-71. Chinese vessels have preferential Hormuz access through Iran's relationship-based transit system. China gets feedstock. Its competitors don't. The crackers that are running are Chinese. The market share being gained during the crisis won't reverse when the crisis ends — capacity closed elsewhere is gone.
The lag
North America has the surplus. Asia has the shortage. Why can't the surplus flow to fill the gap?
It can — slowly. Houston to Busan is 30+ days by sea. Specification differences between NA ethane-derived PE and Asian naphtha-derived grades require converter retooling. Contracts need renegotiation. Asian converters are adapting — CaCO3 filler loading increased from 10% to 25-30%, recycled resin is now cost-competitive against virgin — but these are survival measures, not supply restoration.
Dow estimates 275 days from Hormuz reopening to supply chain normalization: six months of mine clearance, one to two months of carrier and insurance normalization, then force majeure unwinding, inventory rebuilding, and logistics restoration. The damage zone extends months past any ceasefire.
The map
Hormuz doesn't disrupt "polymers." It selectively disrupts polymers based on what the cracker eats. Ethane-based production is immune. Naphtha-based production is crushed — unless you're China, in which case the filter lets your feedstock through and shuts off your competitors'. Three pathways, three outcomes, one strait.