To analyze the emergence and development of nationalism, Karl Deutsch switches between two approaches. He most frequently adopts an organicistic, evolutionist orientation that leads him to detect in identity crises the characteristic symptoms of growing pains, which can affect any society undergoing a process of industrialization. At the same time he provides the fragments of a more precise interpretation by seeking to characterize an evolutive tension between economic centers and peripheries. For a proper appreciation of the Deutschian model, the arguments at each stage of his reasoning that contribute to the latter approach have to be isolated, so that a coherent, explanatory whole can later be recomposed.