Power and the Varieties of Order - Liberal Leviathan: The Origins, Crisis, and Transformation of the American World Order - page 49

liberal logics. What are the incentives that dominant states have to sponsor and operate with-
in an agreed-upon system of rules and institutions? And how do shifts in power and strategic
interests alter imperial and liberal logics?
1 Power distributions are defined in terms of the aggregate material capabilities that states possess relative to
other states. This definition of power as material capabilities, rather than power as control over outcomes, follows
the distinction made in the literature of power. See David Baldwin, Paradoxes of Power (New York: Basil Black-
well, 1989). For methodological challenges in measuring and comparing the distribution or concentration of power
in international systems, see James Lee Ray and J. David Singer, “Measuring the Concentration of Power in the In-
ternational System,” Sociological Methods and Research 1, no. 4 (May 1973), 403-37.
2 A peer competitor is a rival state that has the military, economic, technological, and geopolitical capabilities to
match those of the leading global power. A peer competitor to the United States today would be a state that could
project its military force into any region of the world in a sustained fashion and, more generally, compete with the
United States on a global basis. None currently exist. See John Mearsheimer, The Tragedy of Great Power Politics
(New York: Norton, 2001); and Thomas S. Szayna, Daniel L. Byman, Steven C. Bankes, et al., The Emergence of
Peer Competitors: A Framework of Analysis (Washington, D.C.: RAND Corp., 2001).
3 See Kenneth Waltz, Theory of International Politics (Reading: Mass.: Addison-Wesley, 1979), 131.
4 Before a change in terminology by the World Bank, GNI was formerly referred to as gross national product
(GNP). This study cites GNI statistics calculated using the World Bank's “Atlas” conversion factor, according to
the World Bank “to reduce the impact of exchange rate fluctuations in the cross-country comparison of national
incomes.” See World Bank “Methodologies,” http://data.worldbank.org/about/data-overview/methodologies (ac-
cessed July 14 2010).
5 There are many ambiguities in measures of the distribution and concentration of power. As noted, one issue is
how to weight disparities in military spending, which is a reflection of a policy decision and not underlying capacity.
There is also the problem of how to treat empires. If we measure “Britain's” power, do we include India? Finally,
there is the problem of whether to measure power distributions between the great powers or the power capacities of
the leading state (and/or the great powers) in relation to the wider world. The United States may be more capable re-
lative to the other great powers than Britain was in the nineteenth century, but great powers today may be relatively
less capable vis-à-vis the non-great powers taken as a whole. Recognizing that no approach is perfect, this study will
employ consistent and unadjusted measures of the distribution of power across eras, as arguably this facilitates the
simplest comparisons while still capturing major trends.
6 Stephen G. Brooks and William C. Wohlforth, World Out of Balance: International Relations and the Chal-
lenge of American Primacy (Princeton, NJ: Princeton University Press, 2008), 31.
7 As a leading scholar of long-cycle theory notes: “The current U.S. position is unprecedented in some ways.
Two important ones come immediately to mind. One is that the current system leader has no major power rivals.
That condition may be temporary, but it is certainly unprecedented. It is also closely related to the unipolar outcome.
The emergence of a genuine rival may end US military unipolarity, although there are other ways that the unipolar
status may end. A second novelty is that the United States currently possesses the world system's lead army—not
necessarily in size but in terms of lethality, technological competence, and ability to project force at long distance.
Not all of these characteristics are entirely novel, but the total package is unusual. Normally, the leading whale is not
also the leading elephant.” William R. Thompson, “Systemic Leadership, Evolutionary Processes, and International
Relations Theory: The Unipolarity Question,” International Studies Review 8 (2006), 14.
8 This empirical depiction of American unipolarity draws on work by William C. Wohlforth. See Wohlforth, “St-
ability of a Unipolar World,” International Security 21, no. 2 (Summer 1999), 5-41; Wohlforth, “U.S. Strategy in a