Fragmented by geopolitical tensions, power rivalries and the rise of sovereignist logics, multilateralism is losing ground. States now favour more direct, often bilateral, approaches to fragmented global governance. The multilateral system, embodied by institutions such as the United Nations, is going through a profound challenge. Disagreements between major powers, blockages in international forums and successive crises – health, climate or security – have revealed its operational limitations. The Covid-19 pandemic, in particular, highlighted the inability of collective mechanisms to effectively coordinate global responses. In this context, several States are now challenging the legitimacy and effectiveness of these post-war frameworks. This weakening is accompanied by a rise in unilateral and bilateral logics. Increasingly, States favour direct agreements, tailored to their immediate interests, rather than multilateral compromises deemed too binding. ...