Replacing men with machines makes it possible to limit the number of victims on the side of the person who has them," Morgane Tual points out in an article in Le Monde, dated 27 July 2015.

The journalist's quotation serves as a pretext for his column, which refers to an open letter that has just been published, following an international conference in Buenos Aires. During the conference, more than a thousand personalities, the majority of them researchers in Artificial Intelligence (AI) and robotics, called for a ban on autonomous weapons. The latter fear an "arms race" in this field which, unlike nuclear weapons, does not require "any basic equipment that is expensive or difficult to obtain". The signatories of the manifesto warn that such technology in the hands of dictators and terrorists is only a matter of time. It is therefore urgent to nip such experiments in the bud.

This issue of the prohibition of autonomous lethal weapons was also the subject of a UN meeting in April of the same year. Its rapporteur has long advocated a moratorium on the development of systems, pending an appropriate legal framework. Still others agitate over the lack of "legal responsibility" for the actions of killer robots.

This kind of "raising of shields" is not new in history. Historically, the newest weapons produced by the war industry have been stigmatized. The Spartans considered the war machines as "graves of bravery", the Germans considered the arrow and slingshot as dishonourable ... the feeling of l’honneur and la morality have always taken offence, only to capitulate later and seek to re-establish a new distinction between the honourable and illegitimate use of existing weapons.

Thus it has been l’arbalète in its time. In the West, in the Middle Ages, it was called l’arme of the devil. In Europe, it already equipped the Roman and Carthaginian armies, but developed especially from the 10th century 1.

It is a bow mounted horizontally on a carriage (the arbor), allowing shorter but thicker lines to be fired than arrows (squares), and therefore flying straighter. Initially, it is intended for hunting, because of its precision and power, allowing the flights of the tiles not to be hindered by the foliage of the trees. Their tips can be fitted with a wide variety of points, depending on the target. For example: the dondaine is intended to make the tile heavier and thus increase its penetration force. With the tranchoir, Flat and wide point, the line is intended to neutralize the opposing horses. The vireton, whose tail is helical, gives the tile a rotation during its flight which again increases the penetration force. Thus, no armour resists and its precision is such that a good shooter can reach his target at a distance of 300 m 2 . A week is enough to train an honest shooter 3. Over the ages, several mechanisms have been used to band the bow and speed up the reloading of the weapon, making it easier to use. But the crossbow is only capable of straight shots and only allows a rate of three squares per minute (the bow has a rate of ten arrows). Therefore, if the enemy is charging, crossbowmen can only fire one or two shots before retreating. Similarly, it is heavy and cumbersome 4.

4. Thus, this precise weapon, easy to use and particularly powerful, allowed a low extraction person (commoner) toto shoot down a (noble) knight, i.e. a representative of authority, whose profession of arms had required years of training. This is too much for the Nobility who appealed to the Church. A decision of the Second Lateran Council, held in 1139 under the presidency of Pope Innocent II, forbade the use in wars between Christians of the bow and crossbow, which were considered as weapons of war. perfidious and deadly5. Killing from a distance is not a game. This decision is part of a series of measures taken by the Church to alleviate the evils of war which it recognized it was powerless to remove6. The aim is therefore above all ethical: the human will to save lives in combat7.

However, the Council in question does not prohibit the use of arba- lète against infidels. In fact, Richard the Lionheart, during the Third Crusade (1189-1192), took a contingent of 1,000 crossbowmen with him to the Holy Land. In reality, even in Europe, the ban on crossbows was not respected. Richard the Lionheart, back in France, enters the fight against Philippe Auguste. He used the crossbow against the French, with as few scruples as if he had been dealing with the Saracens8! The council of 1139, however, threatened excommunication, not only to the users, but also to the manufacturers of this formidable weapon. Indeed, what punishment could be more terrible than excommunication in the twelfth century? The excommunicated could not receive the sacraments and thus extreme unction, which made him damned for all eternity! When Richard the Lionheart was mortally wounded in 1199... with a crossbow, which shattered his knee and in passing killed his horse, at the siege of Châlus (Haute-Vienne), some saw it as a providential punishment9.

History teaches us, therefore, that as early as the Middle Ages, ethical considerations and attempts to provide a legal framework were combined in order to limit the development of a technology that was then considered to be the most formidable. The barriers set up to secure its use did not stand up to the pragmatism of the man who justified: "force is just when it is necessary" (Nicolas Machiavelli).

In the 21st century Serge Leblal, editor-in-chief of IT News Info, referring to the open letter quoted in the preamble, names, not without a certain malice, his editorial: "the Council of Buenos Aires calls for a ban on autonomous killer robots". It obviously refers to the one that, nine centuries earlier, claimed to have an action on l’arbalète with the same results?

1 It may have originated in China. Recently, one was found at the Xian site in Shaanxi province, which is 2,200 years old.

2 It has a range of up to 450 m.

3 It takes several years to train a good archer.

4 It will be replaced by the musket, although it will not disappear completely, since in the 21 st century it is still used by special forces.

5 All things considered, this weapon could be similar to the PGM Hecate II. It is amusing to point out here that the use of this precision rifle

(calibre 12.7 mm), is listed in the RETEX on Côte d'Ivoire as not to be used .

6 During the same council, it is decided that tournaments are forbidden, under penalty of deprivation of Christian burial. Knights do not hold any

account for this decision.

7 The oldest of the measures is the Truce of God, which consists of a temporary ban on all military activity during the year.

8 The French refuse to do so; they are the only ones! However, France was not reluctant to use Genoese crossbowmen in its army (Crécy 1346,

Azincourt 1415).

9 Much later, in 1420, Joan of Arc was wounded in the shoulder with a crossbow. The weapon remained in use until the middle of the 16th century. In 1812, in her

Carnot (1753-1823) advocated the use of the crossbow, which he said "could replace small firearms.