[ajross]

Exactly. This is a pipeline architecture, you don't buffer more than absolutely necessary. What matters is how much fuel is flowing, not what the storage fill size is.

Right now it seems like we've entered a detente where (1) Iran controls the strait and allows oil to flow with tolls and (2) the US lies about it and pretends (for domestic consumption) like it's interdicted all tolled commerce.

[mandevil]

Jet fuel in particular is more complicated than that. At the moment, most of the shipping passing through the straits are coming to and from Iran. I believe only a few ships for other countries have transited, none of them tankers- the GCC countries are not willing yet to acknowledge Iran's control over the Straits, since doing so would be to admit that this war was a giant catastrophe.

Iran, for sanctions related reasons, is unable to make international grade jet-fuel. Only the GCC countries can (in the Persian Gulf). And so not a single tanker of jet fuel has transited the Straits of Hormuz to Europe since this incredibly dumb war started. Iran does export raw crude to China, which refines it to international grade jet fuel, and China is getting some shipments from Iran, but China's raw crude imports have dropped, and they have responded by ending jet-fuel exports to the rest of Asia.

My understanding is that Europe can produce jet-fuel from the North Sea deposits, but they rely on imports because it is not sufficient for their consumption (My memory is that 'domestic production' was on the order of 60% of consumption). So as long as the Straits are blocked to GCC traffic there will be problems for European commercial aviation, getting worse over time.

[ajross]

Is there a cite for that explanation? That doesn't sound right to me. My understanding is that almost all Hormuz oil is crude, the refineries are elsewhere.

[mandevil]

Which part? That GCC countries export refined Jet-A? Kuwait was responsible for 15% of seaborne jet fuel exports in 2025 (1), something like 10% of the world's total exports. In 2024, Bahrain exported 20 million barrels of jet-a (2). South Korea, #1 in the world, exported 90 million barrels in 2025- all by sea- (3), so Bahrain isn't a dominant player, but it's still an important amount.

Obviously most of ROK's oil was crude imported to South Korea for re-export elsewhere, but the GCC has spent the last few decades trying to get up the value chain of petro-chemicals and capture more of the value themselves.

1: https://www.vortexa.com/insights/jet-fuel-margins-hit-record... 2: https://www.data.gov.bh/explore/dataset/petroleum-products-e... Note that Bahrain's data explorer doesn't cover 2025, just 2024. 3: https://koreajoongangdaily.joins.com/news/2026-04-07/busines...

[ajross]

Yeah, those number seem cherry-picked. The fact that refineries exist in gulf isn't saying that refinery capacity doesn't exist elsewhere to manage the crude that is transiting the straight. It doesn't mean they do either, but I'd want to see a deeper analysis than any of that stuff you're linking.

Supply chain management is hard, but it's not nearly as fragile as people tend to fool themselves into thinking. How many chip or egg shortages have we lived through which showed up as pretty routine price disruption? And that's especially true in areas like fuel, which everyone recognizes as national security issues worthy of careful study and planning.

My gut says that's bunk, basically. Europe isn't running out of fuel.