In the flurry of mildly interesting disclosures from the Iranian military exercise this week, one is likely to be overlooked. Iranian state media report that on Friday, April 23, the Revolutionary Guard’s naval arm stopped two ships for inspection in the Strait of Hormuz. The ships, according to Iran’s Press TV, were French and Italian. The photo accompanying the story depicts a Kaman-class guided-missile patrol boat on which the boxy, Chinese-designed C802 anti-ship-missile launchers can be seen amidships. The stated purpose of the inspections was to verify “environmental compliance.”
The names of the foreign ships were not provided; sketchy details make it difficult to be certain exactly where in the strait they were stopped. But European ships — even private yachts — rarely venture outside the recognized navigation corridors in the Strait of Hormuz. If this news report is valid, it almost certainly means that Iran detained ships that were transiting those corridors.
That, as our vice president might say, is a big effing deal. That’s not because Iran has committed an act of war by intercepting these ships, as some in the blogosphere are speculating. The intercepts were not acts of war. The purpose of verifying environmental compliance is one Iran can theoretically invoke on the basis of its maritime claims lodged with the UN in 1993. Ironically, however, Iran has never signed the Law of the Sea Convention (UNCLOS), the instrument by which the terms of its claims are defined. Many nations, of course, have yet to either sign or ratify UNCLOS, America being among them. In the meantime, world shipping has operated in the Strait of Hormuz for decades on the basis of UNCLOS’s definition of “transit passage,” which has customarily immunized ships in routine transit through straits against random intercept by the littoral navies (e.g., Iran’s or Oman’s).
Iran would be breaking with that custom by stopping ships for inspection in the recognized transit corridors. But this venue for a newly assertive Iranian profile is chosen well: stopping foreign ships that are conducting transit passage is uncollegial and inconvenient for commerce, but it is not clearly in breach of international law.
What it is, however, is an incipient challenge to the maritime regime enforced by the U.S., which includes the quiescent transit-passage custom on which global commerce relies. Mariners take care to observe the law as it is written, regardless of their nationality or national position on UNCLOS; but the guarantee of their unhindered passage isn’t international law, it’s the U.S. Navy. Demonstrations of force are required only rarely. Reagan put down revolutionary Iran’s only serious challenge to international maritime order back in 1988, in the final months of the Iran-Iraq War. Since then, Iran has refrained from unilateral action against shipping in the recognized transit corridors of the strait.
It’s ingenious to use environmental inspection as a pretext for establishing a new regime of unilateral Iranian prerogative. Iran is probing the U.S. and the West with this move. Fortunately, for the time being, diplomacy is the ideal tool for making it clear to Iran that the U.S. won’t tolerate capricious interference with shipping in the Strait of Hormuz. This initiative of Tehran’s must be nipped in the bud promptly, however. It can only escalate — and without pushback, it will.