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We are all familiar with the popular and academic analyses of the ongoing and future ascent of China. Two of the associated questions are whether and when China might succeed the United States as the lead state in the world system. These are interesting questions, albeit ones that are not likely to be answered in the immediate future. An alternative focus examines instead periods of systemic transition - eras in which it is conceivable that a new leader might emerge at the expense of an older system leader. Framing the question this way presumes that a) future systemic transitions remain a possibility and b) transitions do not occur abruptly but may require several decades to set up structural situations in which a transition might take place. Neither of these assumptions are carved in stone and are open to question. It may be that future systemic transitions are unlikely. Or, it may be that they will not occur as they have in the past. All of these possibilities are assessed from a variety of different perspectives.

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How Might We Know a Systemic Transition is Underway? Clues for the 21st Century; W.R.Thompson PART I: PAST Relative Decline: Why Does it Induce War or Sustain Peace?; S.Chan & B.Tessman State Type and Transitions in Hegemony: The Impact of Technologically Driven Geopolitical, Economic, and Politico-Military Boundary Problems; P.J.Hugill Structural Preludes to Systemic Transition Since 1494; W.R.Thompson Falling Down: An Empirical Test of Dynamic Differentials Theory, 1500-1999; M.Lee PART II: PRESENT Searching for Changing Organizational Architecture During Global Transitons: Where is the Post-Cold War Order?; T.J.Volgy , K.A.Grant & E.Fausett Whether and How Global Leadership Transitions Will Result in War: Some Long-term Forecasts from the Steps-to-War Explanation; J.Vasquez Implications of Asia´s Rise to Global Status; J.Kugler & R.Tammen Kantian Dynamics and Systemic Transitions: Can International Organizations Influence U.S.-China Conflict?; D.Rapkin & W.R.Thompson Explorations of Connections Between Energy Use and Leadership Transitions; D.J.LePoire PART III: FUTURE The Evolutionary Trajectory of the World System Toward an Age of Transition; T.C.Devezas Cities in Transitions and Transformations: Exploring a Jacobsean Approach to Macro-Social Change; P.J.Taylor Scale Transitions and the Evolution of Global Governance Since the Bronze Age; C.Chase-Dunn , R.Niemeyer , A.Alvarez & H.Inoui

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WILLIAM R. THOMPSON is Rogers Professor of Political Science at Indiana University, USA. He is the co-author of Strategic Rivalry: Space, Position and Conflict Escalation in World Politics (2007) and co-editor of Globalization as Evolutionary Process: Modeling Global Change (2008).

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