Does public international law still exist?
In 2026, the answer is no longer entirely clear.
For that matter, do we even remember what public international law actually is?
A unique branch of law, public international law encompasses the body of legal rules governing States, international organizations, and the relationships that bind – or divide – them. Unlike any other legal system, however, it does not impose itself upon its own subjects.
Its effectiveness depends entirely on the voluntary consent of sovereign States. Sovereignty remains its cardinal principle – a principle with two dimensions: complete authority within a State’s own borders and, externally, the assumption of perfect legal equality between all States.
That consent is expressed through the signature and ratification of international treaties – sometimes followed, depending on the constitutional system, by their incorporation into domestic law. It is also expressed through membership in international organizations such as the United Nations.
Our deeply human longing for justice tempts us to believe that this elegant architecture of States and international institutions functions harmoniously, governed by legal rules and mutual respect for sovereignty.
Unfortunately, reality is far less reassuring.
Some international organizations simply have no authority in certain countries because those States have chosen not to join them.
Likewise, many international treaties have no binding force within particular jurisdictions because they are never signed, ratified or incorporated into domestic law – even though those same States are formally parties to such treaties.
Above all, it is easy to forget that public international law does not abolish the law of the strongest. It merely seeks to frame or restrain it.
Some States possess military capabilities vastly superior to those of others. The external sovereignty that international law presents as implying perfect equality between States exists, in practice, largely on paper.
We shall return to this point.
From a historical perspective, public international law, as we know it today, is surprisingly young.
The Renaissance undoubtedly laid some of its intellectual foundations, notably through the emergence of the modern concept of the State. Yet those foundations remained deeply rooted in Christendom, drawing both their moral legitimacy and their limitations from religion. War itself could still be justified whenever Christianity was perceived to be under threat.
The turning point came in 1648 with the Peace of Westphalia. The three treaties that ended two devastating conflicts which, through shifting alliances, had engulfed much of Europe gradually emancipated international relations from religious authority. They initiated the slow secularization of diplomacy and affirmed the internal and external sovereignty of States, legally equal to one another according to the understanding of the seventeenth century.
The Westphalian system became the cornerstone of a long process that would eventually give birth to modern public international law, reaching full maturity only after the WWII.
Determined never again to plunge humanity into a global catastrophe, the victorious powers built both international and European institutions designed to preserve peace.
Founded in 1945, the United Nations was entrusted with preventing armed conflict and maintaining international peace and security. Six years later, in 1951, the European Coal and Steel Community – the forerunner of today’s European Union – was established to make another European war materially impossible.
The failure, in 1954, of the proposed European Defence Community deprived Europe of a supranational army. European security would henceforth rely largely on NATO, the Atlantic alliance that became the military pillar of the Western world. In many respects, the transatlantic alliance was forged through that very failure.
The concepts of war and armed conflict, however, began to evolve almost immediately after WWII.
From 1947 onwards, the Cold War between the United States and the Soviet Union fundamentally redefined the very meaning of war. No longer did it consist primarily of direct armed confrontation between sovereign States. Instead, war became a permanent possibility – a nuclear balance of terror – combined with an ideological struggle extending far beyond the battlefield into economics, culture, science, sport, diplomacy and the media.
This marked the emergence of what is now commonly referred to as lawfare: a multidimensional conflict in which legal instruments, economic coercion, information warfare, sanctions, cyber operations and political influence become weapons in their own right. Armed conflict no longer disappeared; it merely ceased to be its only form. This new kind of warfare would continue to flourish long after the gradual collapse of the Eastern and Western blocs.
Meanwhile, the very institution created to safeguard international peace – the United Nations – gradually lost much of its authority.
Increasingly unable to restrain the law of the strongest, the UN has struggled to fulfil the mission for which it was created.
Faced with military interventions undertaken without Security Council authorization, it has often appeared powerless. The United States and the United Kingdom invaded Iraq in 2003; Russia intervened in Georgia in 2008 and launched its full-scale invasion of Ukraine in 2022; the United States, the United Kingdom and France conducted military operations against ISIS in Syria from 2014 onwards; Turkey has carried out repeated military incursions into northern Syria since 2016.
Each time, the States involved invoked arguments that are legally recognizable in principle yet often far less convincing in practice: the inherent right of self-defence, humanitarian necessity, the prevention of terrorism, the elimination of weapons of mass destruction or chemical weapons, or the protection of peacekeeping forces.
Among these justifications, none illustrates the growing elasticity of legal language better than the notion of preventive self-defence.
The expression is, strictly speaking, oxymoronic.
Self-defence, at least under French law – and indeed under the legal systems of many democratic States – is by definition a response to an imminent threat. It is reactive, not preventive. Preventive self-defence begins to resemble something entirely different: a justification for striking first.
The erosion of the United Nations did not begin yesterday.
What has changed is that questionable military actions are no longer even cloaked in the language of restraint. The escalation of rhetoric now mirrors the excess of power.
The law of the strongest – the very principle that international law was designed to contain – has returned with renewed force.
Greenland has attracted Washington’s attention since 2019. By 2025, the United States was no longer ruling out the use of economic pressure – or even military coercion – to secure control over this autonomous territory, despite the fact that it remains part of the Kingdom of Denmark.
That same year, Washington likewise refused to exclude economic or military pressure to regain control of the Panama Canal, which has belonged to the Republic of Panama since December 1999.
In 2026, a South American political leader was abducted on his own country’s territory in blatant disregard for the principle of sovereignty and transferred to the United States to stand trial before an American court whose jurisdiction is questionable, provoking remarkably little international protest.
That same year, however, another strategic maritime passage proved far less susceptible to American ambitions: the Strait of Hormuz.
Whether coveted, contested or conquered, these territories all share one characteristic. They are rich in hydrocarbons and critical minerals, or they occupy positions of exceptional strategic importance for global trade.
Because trade – or business, if one prefers – ultimately rules the world behind the scenes.
The permanent coup is carried out not by elected governments but by the great predators so vividly described by Giuliano da Empoli in The Hour of the Predators. Yet, as so often throughout history, it is ordinary people who bear the cost.
Editor’s note: Here I am in a restaurant that used to be called the Russian House but changed its name at the start of the Russo-Ukrainian conflict to the Revka House. I don’t know if there’s any connection between the name change and the conflict but the truth is that the change struck me.
Vintage top from the 20s from Marcel & Jeannette, Paris Flea Market – Dior skirt – Repetto shoes – Tom Ford sunglasses – Lanvin purse
June 26, 2026
