SHIPS of any sovereign state have the right to freedom of navigation. Except when they don’t.

The entitlement is explicitly spelled out in Article 90 of the United Nations Convention on the Law of the Sea. Ironically, much of the rest of the document is dedicated to setting out the circumstances in which the prerogative doesn’t hold.

Just about everybody in the industry would agree the principle is a good one. Indeed, to allude to another declaration promulgated two centuries previously, most of us would hold this truth to be self-evident.

Unclos is one of the most widely ratified treaties in existence. It has garnered a substantial body of case law on its application, making it perhaps the very cornerstone of the wider system of international law.

Yet nobody is a freedom of navigation absolutist, in the same sense that world’s richest man is a freedom of speech absolutist, or at least likes to think he is. It remains a diplomatic compromise, painstakingly hacked out in various iterations over eight decades.

The needs of world trade are delicately balanced against the needs of states to undertake fishing, scientific research, mineral exploitation and crime prevention, and uphold security concerns.

There are always going to be circumstances in which raison d’état will override the needs of brute commerce. Let them be limited and somewhat rare.

As Lloyd’s List has argued this week, the freedom of navigation gold standard which most of us have come to recognise as the norm throughout our working lives is these days looking decidedly shopworn.

Recently it has most obviously been assailed by the Houthi onslaught against merchant tonnage in the Red Sea.

As we pointed out, the Somali piracy crisis elicited a united response from the international community. Navies from the US, Russia, China, the EU, India and Iran patrolled large tracts of the Indian Ocean, putting aside political differences for the wider common good.

Would that we had seen such a healthy reaction to the challenges of the past 17 months. What we have witnessed instead is fragmentation, with warships on the scene protecting solely their own national interests.

The Houthis consider themselves to be the legitimate government of Yemen, a claim recognised elsewhere only by Tehran. If they are remotely serious in the quest to convince others of their right to the title, they could start by observing their obligations under Unclos, to which Yemen is a signatory.

Hint: this entails not launching missiles and drones to strike vessels with the right of innocent passage.

Five thousand miles further east, China routinely harasses civilian shipping as it seeks to assert control of various largely uninhabited islands in the South China Sea.

Japan, Brunei, Indonesia, Malaysia, the Philippines, Taiwan and Vietnam demur in whole or part. The resultant clashes have sometimes turned ugly and even led to loss of life.

China has said publicly that it no longer endorses Unclos as the single authoritative source on the law of the sea and has rejected Unclos arbitration as a potential means of resolving its territorial disputes with its neighbours.

More worryingly still, there is now a prospect that Russia could become the first country ever to withdraw from the convention. As article 317 expressly sets out, signatories have the right unilaterally to abrogate the treaty, without having to give reasons.

Moscow’s disaffection is said to stem from its ejection from International Maritime Organization council in the wake of its invasion of Ukraine, and a desire to declare the Sea of Azov and perhaps even the Arctic to be Russian internal waters.

Neither of those latter proposals would be good news for shipping. But were Putin to enact them, perhaps by way of a display of bare-chested horseback militarist machismo, there is no obvious means of preventing him from so doing.

Decades of relatively harmonious multilateral governance of the oceans seems to be crumbling before our eyes. The danger is that the world would then drift towards a multiplicity of competing legislative frameworks.

This would visit chaos on trade, maritime safety and sustainability, not to mention myriad other areas from territorial claims to deepsea mining, at a time when shipping will be making the transition to uncrewed vessels.

It’s still not too late to avert this calamitous outcome. But let go of Unclos and we might never get freedom of navigation back.