Five months after Israel and the United States launched strikes that killed Iran's Supreme Leader and ignited a wider war, the Strait of Hormuz has become the conflict's most stubborn front, a 21-wide chokepoint where military power and diplomatic paralysis meet.

The pattern by mid-July had become grimly familiar. The US hit Iranian military targets, coastal radar, drone sites and missile infrastructure night after night, describing each round as necessary to protect commercial shipping.

Iran answered by striking tankers, including two vessels flagged to a Gulf ally that were hit inside Omani waters, and by insisting, at various points, that the strait was closed to traffic it hadn't authorized.

A ceasefire brokered earlier in the spring collapsed; indirect talks fell apart; both governments' leaders traded public threats. This is no longer a slow-burning standoff. It is an active, if intermittent, war being fought largely through the strait itself.

Why can neither side simply win here? Military logic explains the deadlock better than anything else.

Washington has the firepower to degrade Iran's coastal defenses and has done so repeatedly. But US Vice President JD Vance put his finger on the underlying problem: you can strip away radar, drones, and missiles, and Iran can still threaten shipping with small boats, mines, and short-range fire, an asymmetric tactic that doesn't require the capabilities the US keeps destroying.

Iran, for its part, cannot hope to defeat the US Navy or hold the strait closed indefinitely; a genuine closure would cut off its own oil exports and invite even harsher retaliation. What both sides can do is make the strait too dangerous to be useful, which is functionally what has happened; commercial transits have slowed to a fraction of normal levels.

Diplomacy keeps failing for structural reasons, not just bad timing. Tehran's foreign ministry has said flatly that it has no plans to negotiate, and past rounds of indirect talks broke down before producing anything durable.

Part of the difficulty is that the war has generated new points of friction faster than old ones can be resolved: Iran's floated idea of charging tolls for transit through the strait — which it frames as compensation for "services" it provides, has drawn a blunt rejection from the US and International Maritime Organization, which notes there's no legal basis for one country to toll an international strait.

That toll dispute is minor next to the war itself, but it illustrates how each side keeps introducing new demands that make de-escalation harder to negotiate even when both may want it.

The stakes go well beyond the two belligerents. The strait carries roughly a fifth of the world's seaborne oil and a similar share of global LNG. A multinational Persian Gulf Strait Authority has emerged as an attempt at collective management.