Diffusion of War: Some Theoreticai Considerations and Empirical Evidence

In quantitative research into the causes of war there is a tradition in asking the question whether there is any systematic pattern in time. Do wars come in cycles? Is there an upward trend in the frequency of warfare or are wars disappearing gradually? In addition, some investigations have been made on the war-proneness of nations. Are some nations inclined to fight more than others? Or are chances that states resort to violence equal? Using the data collected in the Correlates of War (COW) Project, this study attempts to test the interactive effects of temporal and spatial aspects of warfare over the period 1816-1980. Results show that outbreaks of war within specific regions (Europe, the Americas, Asia, the Middle East and Africa) are not related to outbreaks elsewhere in the international system. Furthermore, warfare in Europe has a distinct epidemiological character, while in other regions it has not.