Institute of European Studies

The emergence and stability conditions of security communities have been the subject of many studies. The possibility of decay, the factors potentially causing it, and the pattern of a decay process have been largely neglected. This eufunctional bias should be corrected; social institutions, as we know from history, are liable to vanish, and there is no categorical reason why security communities should be the exception. Filling the gap may also be helpful to recognise early indicators for decay and to take countermeasures to prevent it. With this theoretical and practical objectives in mind, the paper develops a theory of decay that relies on the ideational and material factors which resarch has identified as key variables in the process leading to the growth of security communities. Starting from this basis, it identifies changes and sequences of events that could reverse the progressive evolution into its opposite. The model is then applied to three case studies, the Delian League, the Hansa League, and the Concert of Europe. A final look at the present state of the Atlantic Community identifies reason for concern, but not for panic.