Reciprocity in the Field of International Arms Regulation

The question of reciprocity in the field of armaments is particularly paradoxical. On the one hand, humanitarian concerns tend to exclude it. However, the question of the limitation of the means of combat can only be understood within the framework of the relationship it organizes, the military relationship, which is one of hostility and competition. It is therefore difficult to totally exclude any question of reciprocity. If the “si omnes” clause has disappeared from the field of international humanitarian law, the fact remains that reciprocity continues to play an essential role in the field of armaments. The figures can be very numerous, from the search for a strict balance (see the Start Treaty) to normative systems in which reciprocity can be selective or differentiated according to the different actors (see the Non-Proliferation Treaty) or excluded altogether (see the Chemical Weapons Treaty, e.g.). Here it is important to distinguish between several categories of weapons or weapon systems. Two fundamental distinctions must be made. The first concerns conventional weapons and weapons of mass destruction. The question of reciprocity will not be addressed in the same way in both cases, with a much broader prohibition for the latter. The second concerns nuclear weapons, which raise specific issues and therefore need to be given special treatment. Indeed, they do not only refer to the way of conducting armed operations, but constitute a technique that is expected to prevent certain forms of conflictuality. Reciprocity may therefore be excluded in arms regulation in some cases, and there are indeed non-reciprocal commitments. But it can also appear in this area, whether at the level of the conclusion of commitments, their application, and their extinction. Through various “legal strategies,” which it is a question of identifying, states can adapt their legal commitments to the behavior of other states and potential adversaries. State practice reflects this ambivalence in many ways, particularly in the field of military nuclear power.