Eight generalizations are extracted from two partially competing perspectives (Johan Galtung's “feudal interaction” and Jorge Dominguez's “international fragmentation”) on center-periphery interaction patterns. Seven of these generalizations are tested by examining head of state,...

The popularity of Kondratieff long waves fluctuates according to the economic climate. Periods of slow growth help make long wave explanations more attractive. While their popularity may oscillate, the evidence associated with the existence of long waves continues to be disputed. A review of the...

Processes of war, trade, and systemic leadership are often examined in isolation from one another. Sometimes, two of the three are studied together. Does war interrupt trade? Does systemic leadership reduce the level of warfare? Does systemic leadership lead to freer trade? While these are...