International Judicial Monitor
Published by the International judicial Academy of the International Law Institute, Washington, D.C.
with circulation assistance from the American Society of International Law

Spring 2017 Issue

Historic Moments in International Law

“Savage and Monstrous Excesses” in the Age of Reason

Stephen C. NeffBy: Stephen C. Neff, Reader-in- Law, Public International Law, University of Edinburgh Law School

The modern law of armed conflict prohibits, absolutely, the targeting of civilian populations. But it was not always so. In its pre-modern period, the law on the conduct of war reduced, in effect, to a single proposition: that any act which conduced to the attainment of military victory was permissible, while any which did not meet this test was forbidden. In the short, the single principle of military necessity – or, more accurately, military value – held unchallenged sway. So if the targeting of a civilian population was actually of military value in a particular circumstance, then it was allowed. Only gratuitous damage was forbidden.

It is easy to see that much suffering on the part of civilians could occur under such a legal regime – a fact that was vividly illustrated in the late Seventeenth Century in the notorious case of the devastation of the Rhenish Palatinate by invading French forces. It began in 1688, when King Louis XIV of France made what he intended to be a lightning grab of the Palatinate, a small but wealthy and prestigious portion of the Holy Roman Empire located in southwestern Germany, just across the Rhine. It was anticipated to be a short and glorious triumph for the Sun King. Things began well for His Most Christian Majesty, but a series of reversals turned the conflict into a long and grinding war of attrition. (The conflict, incidentally, has gone under a bewildering number of names, including the War of the League of Augsburg, the War of the Grand Alliance, the Nine Years War, the Ten Years War, the Orleans War, the War of the English Succession, King William’s War or the War of the Palatinate, depending on which of the many specific issues is being highlighted.)

The French soon decided to beat a strategic retreat – while, in the process seeking to prevent pursuit by the enemy. The means chosen was the systematic devastation of the Palatinate, to create a barrier between the German forces and the French frontier. This was emphatically not a case of undisciplined or desperate troops going on a rampage of their own. On the contrary, it was a deliberate policy of destruction, planned and ordered from the highest levels. In December 1688, orders came from the French king “to ruin completely all the places that you leave along the upper and lower Neckar so that the enemy, finding no forage or food whatever, will not try to approach there.” The destruction was to be as thoroughgoing as possible – with the sole exception that certain religious buildings would be spared.

Devastation was not confined to crops and rural areas. The French commander in the area proposed that the city of Mannheim be “put . . . to the sword and plough[ed] . . . under.” It was, in March 1689, when it was reported to have been levelled “like a field.”Heidelberg survived, for a time, by virtue of the energetic actions of its citizens, who succeeded, in March 1689, in quenching the fires intended to engulf the town. But it was less fortunate later: in 1693, it too was burned to the ground. Far from showing any remorse at the suffering wrought, Louis XIV proudly celebrated the destruction issuing a medal ominously proclaiming “Heidelberga deleta.” In all, about twenty substantial towns were destroyed, including Worms, Speyer, Bingen and Oppenheim, along with countless villages.

The devastation elicited loud protests, in the form of a torrent of pamphlets, including graphic illustrations, denouncing the French as barbarians and calling for revenge. In fact, the incident marked the effective beginning of feelings of national patriotism on the part of the politically fragmented German population – patriotism with, it may be added, a pointedly anti-French flavor that would endure for many years to come. The whole affair was burned deeply into the German consciousness, to the point that the centenary, in 1789, was marked by the issuing of a fresh batch of pamphlets duly denouncing the barbaric French.

Prior to that, however, the incident had also been recalled, in a calmer setting, by one of the leading writers of international law, the Swiss jurist Emmerich

de Vattel, in his famous treatise on The Law of Nations of 1758. (Vattel, incidentally, was a German subject by virtue of his home town of Neuchâtel being, in his time, a possession of Prussia.) He denounced the French devastation of the Palatinate as an unlawful act. But it is instructive to note the ground for his conclusion.

The French action was illegal, in Vattel’s eyes, not because it breached a general rule against devastation of civilian areas per se, for he was well aware that there was, at the time, no such rule. Ever the humanitarian, Vattel decried the devastation of civilian areas as “savage and monstrous excesses” – but he added the significant proviso, “when committed without necessity!” The true test of legality, then, was the presence or absence of such necessity. And that was, inevitably, a question of fact, viewed in the context of the particular actions in question. Well aware of this consideration, Vattel proceeded to deny that the torching of the Palatinate made genuine military contribution to the French cause. The proferred justification – that the French were defending their own frontier from the Germans – was expressly rejected by Vattel, who insisted that the policy, in reality, “contributed but little” to the defence of France. “The whole proceeding,” he declared, “contributed nothing” to France’s security or military position.It amounted to mere wanton destruction – and, on that basis, was illegal.

Vattel, however, was clearly unhappy at resolving the matter in this way, as a mere question of fact regarding military necessity. He went on to propose an altogether different approach to the laws of war. It would be preferable, he maintained, to govern the conduct of war by means of a fixed code of specific rules, instead of relying on the single all-embracing principle of military necessity.The idea, in Vattel’s words, was to “lay down general rules, independent of circumstances and of certain and easy application.” The result would be that the lawfulness of any acts of hostility would be determined “in the abstract and in their essential character,” and there would be no need “to consider whether the act was necessary, useless or superfluous in a given case.” The adoption of such a fixed code would then enable certain practices – such as the targeting of civilians – to be flatly forbidden, without regard to any military value that they might have. In other words, humanitarian concerns could then be given a higher priority in the laws of war than strictly military considerations.

This is in fact the direction that the modern law of war has taken, in the form of a host of prohibitions of various inhumane practices, without regard to the what military value they might have in particular circumstances. The prohibitions against chemical and biological weapons come readily to mind, along bans on laser blinding weapons, land mines and cluster munitions. In addition, there is, in modern law, an absolute prohibition against the deliberate targeting of civilian populations.

This proposal of a fundamental shift in the laws of war from a universal principle of military necessity to a code-of-conduct approach represents Vattel’s single most important contribution to the development of modern international law. It justifies our regarding him as the father of the modern law of war. Those who wish a fuller exploration of this topic may usefully consult a chapter by (of all people) your humble columnist, in a book entitled Vattel’s International Law in a XXIst Century Perspective (edited by Vincent Chetail and Peter Haggenmacher, 2011).

It only remains to note that Vattel’s vision of completely supplanting military necessity by a fixed code of conduct is far from complete even at the present time – and, given the ever-changing nature of warfare, will ever remain so. In a host of ways, we still rely on the principle that certain acts of war are not prohibited per se, but become unlawful if they lack military value in the particular circumstances in which they are used. This point was illustrated in the Oil Platforms Case of 2003, when the World Court held it unlawful to attack a mere “target of opportunity” which was lacking in military value, even though there was no use of prohibited weapons. Regarding the targeting of civilian populations as such, however, there is an explicit, and non-derogable, prohibition, without regard to military value. Would-be modern Sun Kings who engage in such practices are, sadly, not lacking. But they act at their peril.

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© 2017 – The International Judicial Academy
with assistance from the American Society of International Law.

Editor: James G. Apple.
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