For months, publicly visible shipping data from the Strait of Hormuz has told an alarming story.

Tankers have disappeared.

Commercial traffic has fallen to a fraction of its pre-war level.

Major Chinese shipping companies have stopped sending vessels through the waterway.

Iran says the Strait remains closed.

Yet something has never quite added up.

If Hormuz is effectively closed, how is so much Middle Eastern oil still getting out?

We may now have part of the answer.

The United States military has reportedly been running a previously undisclosed operation enabling oil tankers to move through the Strait of Hormuz despite the Iran conflict.

According to Axios, citing US officials, approximately 15 to 20 oil tankers a night have been moving through the waterway under an operation coordinated by the US military.

The operation reportedly facilitates both loaded tankers leaving the Persian Gulf and empty vessels travelling in to collect crude from producers.

If those figures are accurate, the implications are enormous.

The Strait of Hormuz may appear almost closed when viewed through normal commercial shipping data.

But beneath the visible traffic, a substantial quantity of oil may still be moving.

And that may be one reason the global energy crisis — and Australia's fuel crisis — has not become considerably worse.

The numbers appeared contradictory

Reuters reported this week that conventional tracking data recorded only six commodity-vessel crossings through Hormuz on Tuesday, down from nine on Monday.

Before the Iran war, the Strait carried about one-fifth of global oil and LNG movements.

The difference between the old and new traffic levels has been extraordinary.

Yet the global economy has continued functioning.

Asian refineries have continued receiving crude.

Middle Eastern producers have continued exporting at least some oil.

Australia has continued obtaining petrol, diesel and aviation fuel.

Brent crude has risen substantially but has not reached the catastrophic levels that might reasonably have been expected from the prolonged effective closure of one of the world's most important energy corridors.

There had to be more happening than the publicly visible vessel movements suggested.

Apparently, there is.

A protected corridor through the Strait

Axios reports the US operation is being coordinated from Fort Bragg in North Carolina and involves protecting the movement of tankers through Hormuz.

US officials say approximately 15 to 20 tankers are travelling through each night.

The reported operation is considerably more sophisticated than simply escorting loaded tankers out of the Gulf.

Empty vessels also need to get in.

That distinction is important.

An oil producer cannot continuously export crude if tankers leave but replacements cannot enter.

The international petroleum system requires circulation.

Empty tanker enters.

Crude is loaded.

Loaded tanker leaves.

Another tanker replaces it.

If either side of that movement stops, eventually exports stop as well.

The US operation reportedly attempts to preserve both.

Why hasn't everybody seen these ships?

That is one of the most interesting aspects of the story.

Modern commercial ships normally transmit information through the Automatic Identification System, or AIS.

That allows vessels to be tracked.

Shipping companies use it.

Ports use it.

Analysts use it.

Journalists use it.

And websites allow ordinary members of the public to follow ships around the world.

But vessels operating in dangerous circumstances may reduce or disable normal transmissions.

There are legitimate security reasons for doing so.

A ship continuously broadcasting its exact position in a war zone can effectively tell an attacker where to find it.

That means publicly available ship-tracking information can provide an incomplete picture during conflict.

The enormous discrepancy between visible Hormuz traffic and the movements described by US officials may partly reflect that reality.

The oil market has been telling us something

There has been another clue.

Price.

Brent crude settled at US$91.62 a barrel on Wednesday, its highest close since July 24.

That is expensive oil.

But consider the circumstances.

A war involving Iran and the United States.

Severe disruption in Hormuz.

Attacks on tankers.

Middle Eastern production losses.

Falling inventories.

Expensive freight.

Disrupted Russian refining.

Diplomatic negotiations failing.

And one of the world's most important energy corridors apparently operating at a tiny fraction of normal capacity.

Under those circumstances, the fact that Brent is around US$92 rather than vastly higher requires explanation.

Alternative supplies provide part of it.

US crude has moved to Asia.

West African oil has moved east.

Saudi Arabia has developed alternative export arrangements.

The UAE has used Fujairah.

Iraq is creating new mechanisms.

China has adjusted its shipping.

And now we apparently know something else.

Oil has continued moving through Hormuz itself.

That may have prevented a much larger price shock

The US officials cited by Axios argue that the operation has helped prevent oil prices from rising substantially further.

That proposition is economically plausible.

Every tanker that successfully leaves the Gulf increases the amount of oil available to the international market.

Every empty tanker that successfully enters creates capacity for another cargo to leave later.

Additional supply reduces scarcity.

Reduced scarcity restrains prices.

The protected corridor does not need to restore pre-war volumes to make a difference.

Even partial flows can substantially change the balance between supply and demand.

That is particularly important in a market operating with depleted inventories.

Australia benefits indirectly

There is a direct Australian consequence.

Australia imports most of the refined petroleum it consumes.

Much of that fuel comes from Asian refineries.

Those refineries need crude.

If Middle Eastern crude continues reaching Asia, the refineries producing petrol, diesel and aviation fuel for regional customers — including Australia — have more feedstock available.

That reduces the danger of a severe physical shortage.

Australia may therefore be benefiting from an operation most Australians did not know existed.

We should distinguish between supply and price

This does not mean Australian fuel should suddenly become cheap.

Quite the opposite.

The international system is still operating under extraordinary pressure.

Brent is above US$90.

Tanker freight is expensive.

War-risk insurance is expensive.

Diesel refining margins have reached exceptional levels.

Jet-fuel supplies remain constrained.

Inventories have been depleted.

Australia still has to transport refined products enormous distances.

The reported US corridor helps answer one question:

Can enough oil continue moving?

It does not automatically answer another:

Can it move cheaply?

Diesel remains Australia's larger concern

That distinction is particularly important for diesel.

The world may have enough crude.

But the global refining system remains constrained.

Middle Eastern refinery disruption has reduced output.

Russian refinery attacks have reduced another important source of diesel.

International refining margins have surged.

Australia therefore faces a peculiar situation.

More crude moving through Hormuz can reduce the risk of outright energy scarcity without immediately solving the shortage of finished diesel.

That is why Australians should not expect every improvement in crude supply to produce an immediate fall at the pump.

The petroleum chain has multiple bottlenecks.

Hormuz is only one of them.

Nevertheless, this is good news

After months of escalating risk, it is important to recognise a development that potentially improves Australia's position.

If the United States can maintain a reasonably reliable protected tanker corridor through Hormuz, the consequences could be substantial.

Gulf producers can export more oil.

Asian refiners gain more reliable supply.

Alternative crude premiums could eventually ease.

Global inventories have a better chance of stabilising.

The risk of extreme oil-price spikes diminishes.

And Australia gains another layer of protection against serious fuel disruption.

It does not solve the crisis.

It makes the crisis more manageable.

The world now has three strategies

The international response to Hormuz increasingly appears to have three distinct components.

The first is go around it.

Saudi Arabia can move some crude westwards.

The UAE can export through Fujairah.

Iraq is examining additional export routes.

Asian refiners are buying American and African crude.

The second is move the oil to tankers waiting outside it.

Ship-to-ship transfers around Fujairah and Oman allow customers to avoid sending their own vessels into dangerous waters.

The third strategy now appears to be:

Go through Hormuz — but do it under military protection and with reduced visibility.

Together, these mechanisms explain why the global petroleum system has proven so extraordinarily resilient.

Markets are solving an enormous logistical problem

There is a tendency during international crises to focus exclusively on governments.

But businesses have played an enormous role in keeping the energy system functioning.

Oil traders have found cargoes.

Refiners have changed crude slates.

Shipping companies have changed routes.

Tankers have repositioned.

Insurers have priced extraordinary risks.

Producers have changed export points.

Governments have released reserves.

Military forces have apparently facilitated protected transit.

Each part of the system has adjusted.

The result is imperfect and expensive.

But the oil continues moving.

That resilience has protected Australia

Australia sits thousands of kilometres from Hormuz.

Yet our economy is extraordinarily sensitive to what happens there.

Without these adaptations, Australia could potentially have confronted:

much higher petrol prices;

much higher diesel prices;

serious aviation-fuel pressure;

higher freight costs;

larger inflationary consequences;

greater government intervention;

and potentially physical fuel shortages.

Instead, Australia has largely faced a price and resilience problem rather than a systemic supply failure.

That distinction matters.

The operation carries obvious risks

There is another side to the story.

Moving commercial tankers through an active conflict zone under military protection is inherently dangerous.

Ships have already been attacked.

Crew members have been injured.

Iran continues asserting control over Hormuz.

The United States and Iran fundamentally disagree over the legal and military status of the waterway.

A miscalculation involving a tanker and military forces could produce rapid escalation.

The corridor therefore provides supply resilience while simultaneously operating inside one of the most dangerous maritime environments in the world.

It cannot be regarded as equivalent to normal commercial shipping.

Iran's response matters enormously

The durability of the arrangement will depend partly upon Tehran.

Iran has threatened renewed offensive action if diplomacy fails. Reuters reported this week that Tehran was prepared to adopt a “fully offensive” military stance around Hormuz as the peace process stalled.

If Iran actively attempts to disrupt the reported US-protected corridor, the situation could escalate dramatically.

Conversely, if tanker movements continue without major confrontation, the corridor could become increasingly important to international supply.

The next few weeks may therefore tell us considerably more about whether this is a temporary wartime improvisation or a sustainable mechanism.

China remains cautious

One important indicator is the behaviour of Chinese shipping companies.

Two major Chinese state-controlled operators have stopped sending their own vessels through Hormuz and Bab el-Mandeb.

Instead they have been collecting crude outside the Gulf using ship-to-ship transfers.

Those companies previously carried approximately half of China's Middle Eastern crude imports.

That tells us commercial confidence has not returned.

If some of the world's largest energy shipping companies remain unwilling to send their vessels through Hormuz, the waterway cannot reasonably be described as commercially normal.

A military corridor and a functioning international shipping lane are not the same thing.

Normal shipping remains the objective

The best outcome remains remarkably simple.

Tankers should be able to sail through Hormuz without military protection.

AIS systems should remain switched on.

Insurers should regard passage as ordinary commercial risk.

Shipowners should not have to decide whether crews can safely enter.

Iran and the United States should not be contesting control of the waterway.

Oil should move because customers purchase it — not because warships make the voyage possible.

Until those conditions return, the energy crisis is not over.

But Australia has gained breathing room

That may be the most important Australian interpretation of this development.

A protected tanker corridor buys the international economy time.

It keeps some Gulf oil moving.

That helps Asian refineries.

Alternative supply chains continue developing simultaneously.

Australia is strengthening strategic fuel reserves.

Chinese refined-fuel exports are beginning to recover; Reuters reports China's July refined-oil exports rose 6.7 per cent from June, including a strong increase in diesel exports.

Several different mechanisms are therefore beginning to work in Australia's favour.

None is sufficient alone.

Together they make the system considerably more resilient.

The greatest danger may be complacency

There is a paradox here.

The more successfully the world adapts to Hormuz disruption, the easier it becomes to underestimate how serious the underlying problem remains.

Fuel arrives.

Service stations remain open.

Aircraft fly.

Trucks operate.

Supermarkets receive deliveries.

Eventually the crisis begins to feel less dramatic.

But underneath that apparent normality lies an extraordinary international effort involving alternative oil suppliers, longer tanker voyages, ship-to-ship transfers, strategic reserves, expensive insurance and — apparently — covert military facilitation of commercial tanker traffic.

Normality is being manufactured at considerable expense.

Australia should not confuse that with the return of normal conditions.

The Times View

For months, the numbers did not quite make sense.

Public shipping data showed the Strait of Hormuz operating at a tiny fraction of its pre-war capacity.

Yet enough Middle Eastern oil continued reaching the world to prevent the catastrophic supply shock many feared.

We now have a possible explanation.

US officials say a military operation is enabling approximately 15 to 20 oil tankers a night to move through Hormuz, including both loaded vessels leaving the Gulf and empty tankers entering to collect crude.

If accurate, that is an extraordinary logistical operation.

And Australia may be one of its indirect beneficiaries.

The crude leaving the Gulf helps supply Asian refineries.

Those refineries help supply Australia's petrol, diesel and aviation fuel.

Every additional barrel reduces the danger of physical scarcity and potentially restrains the international price Australia ultimately pays.

But we should not mistake a protected wartime corridor for a reopened Strait.

Commercial traffic remains severely depressed. Major Chinese shipping companies continue avoiding Hormuz. Iran continues threatening escalation. Brent has risen above US$91.

The global energy system has nevertheless demonstrated something remarkable.

When Hormuz became almost unusable, the world went around it.

Now we discover it has apparently also been finding ways to quietly go through it.

That ingenuity may be one reason Australia's fuel crisis has remained manageable rather than catastrophic.

The operation does not make fuel cheap.

It does not end the war.

And it certainly does not make Hormuz safe.

But it may be keeping oil moving.

For an Australia dependent upon international fuel supply chains, that difference matters enormously.