ABSTRACT
On 21 September 2020 a total of 56 former leaders of 22 umbrella states published an open letter in support of the Treaty on the Prohibition of Nuclear Weapons, noting the growing risks posed by nuclear weapons and calling for a reconsideration of policies. They denounced any role for nuclear weapons in the defence of their countries, mainly on humanitarian grounds. The same conclusion can be drawn from within the international security paradigm. For European umbrella countries, the humanitarian approach and the international security paradigm are mutually supporting rather than competing paradigms. A key issue and critical question in the history of North Atlantic Treaty Organization (NATO) is the purported credibility of the roles assigned to nuclear weapons. In Europe, while the number of weapons and host countries has gone down, there is little attention to the broader question of the credibility of the umbrella and, in official circles, an aversion to discussing it. The dilemma facing the umbrella states is a hard one. On the one hand, it is in their interest not to be defended with nuclear weapons. On the other hand, they deem it important to remain members of NATO. These propositions might or might not be compatible.
