Domestic law, case law and policies play a decisive yet underestimated role in ensuring that partnered operations are carried out in compliance with international law. Research on the legal framework of partnered operations has so far focused on clarifying existing and emerging obligations at the international level. Less attention has been devoted to understanding whether and how domestic legal systems integrate international law into national decision-making which governs the planning, execution and assessment of partnered operations. This article tries to fill the gap by focusing on the practice of selected States (the United States, the United Kingdom, Denmark, Germany and Italy), chosen for their recent or current involvement in partnered operations. By using the International Committee of the Red Cross's “support relationships” framework and based on a comparative analysis of practice, the study seeks to evaluate the effectiveness of national laws, case law and policies according to their ability to prevent or mitigate the risk of humanitarian consequences posed by partnered warfare.

The potential use of nuclear weapons has long been a global concern. This article highlights the principal rules of international humanitarian law (IHL) governing the conduct of hostilities applicable to nuclear weapons, and the issues and concerns that would arise were such weapons ever to be used again, in particular the severe and extensive consequences for civilians, civilian objects, combatants and the environment.

In recent years, increased attention has been paid to the humanitarian consequences of nuclear weapons. Based on what has been learned from extensive research on the humanitarian and environmental effects of nuclear weapons since they were first used in 1945, and the accompanying implications for IHL, it seems appropriate to conclude that the use of nuclear weapons in or near a populated area would amount to an indiscriminate attack and that there should also be a presumption of illegality with regard to the use of nuclear weapons outside such areas.

This paper discusses non-State actors’ motivation and capacity to develop and use chemical, biological, radiological or nuclear (CBRN) improvised weapons in attacks, as well as the possible consequences of such use. Six types of groups have been identified as potential CBRN weapons users that may increasingly be able to acquire relevant CBRN weapons-related knowledge, skills and possibly materials. As technical barriers still form a gap between the theoretical possibility and the operational reality, any potential future CBRN attacks would most likely be crude, low-level attacks, including chemical or radiological materials. CBRN attacks carried out by non-State actors in the future are likely to be more disruptive than destructive.