On August 23, 2026, the Iranian Parliament's National Security and Foreign Policy Commission approved Article 3 of the Strategic Action Plan for Security and Development of the Strait of Hormuz. The measure charges ships from "authorized" countries for maritime services during transit, payable in rials or any currency Tehran names. A floor vote is still pending but the Iranians have telegraphed this as the plan all along.

The law would formalize what Iranian forces began in March, when tankers paid reported fees as high as $2 million per passage. Tehran has since massaged the term toll into service charge, but the effect is the same. It's a purposeful dodge of the UN treaty guaranteeing transit through international straits. Iran never ratified this treaty, but legalistic wordplay helps them steer clear of criticism.

But declarations are just words until money changes hands. Let's benchmark what this would mean.

Once, for 428 years. From 1429 to 1857 the Danish crown taxed every ship passing through the Oresund under the guns of Kronborg castle. The Sound Dues supplied as much as two thirds of royal revenue at their peak and financed the Danish state for four centuries. But as usual, history has a lesson to teach us. The toll died when the largest shipper refused to pay.

The United States announced its merchantmen would pass without payment, and Denmark took a buyout in the 1857 Copenhagen Convention. Even Washington settled its own account in a separate treaty weeks later. At the end of the day, business is business and 400 years of tolls was a good ride while it lasted.

The economics of a strait toll are pretty simple. The toll will survive as long as enforcement is cheaper than the revenue it protects. That is at least, until redundancies are built.

This is my rough estimate:

Tehran has two to three years of maximum leverage, then a long decline that never reaches zero. Before the war, about 20 million barrels of oil moved through the strait each day. Bypass pipelines in Saudi Arabia and the UAE now carry an estimated 3.5 to 5.5 million barrels per day, and the war accelerated construction.

The UAE plans to double its bypass capacity to 3.6 million barrels per day by mid 2027, and Goldman Sachs projects pipelines could cover more than 60 percent of pre-war Gulf export volume by the end of 2028. Gas is the exception.

Qatari LNG has no pipeline out, which strands almost 20 percent of global LNG exports behind the strait for as long as Tehran wants. Pipelines also make soft targets, and Iran's Houthi partners sit astride Bab el-Mandeb, the strait the Saudi Red Sea route depends on.

So, we've got a couple of different vulnerabilities here. Qatar is the most dependent on the Strait of Hormuz since they have no path out. Any pipes that transit to the Red Sea are also vulnerable if the Houthis stay firmly in the pocket of Iran.

So, can they keep toll the strait? Yes? Certainly not for 400 years.

Denmark's toll ended when one customer called the bluff and everyone, bluff-caller included, bought out the tollbooth. The Gulf version of that refusal is being poured in concrete on a published schedule. Iran runs the tollbooth. The customers are building the detour.