have tended largely to assume that stability arises where power is dispersed in a
roughly equal manner. They understand legitimacy to pertain to agreement and
consensus, at the very least amongst the major powers, and thus to require some
acknowledgement of the equal status of those powers. Those arguments that dwell
on hegemony, by contrast, consider stability as derivative of the concentration of
power. ‘Fragmentation of power... leads to fragmentation of the international
economic regime’, insisted Keohane, whereas ‘concentration of power contributes
to stability’.^50 Stability, so it would appear, is most likely when there is available a
hegemon, both able and willing to play this role. How is it that two theories, both
concerned with distributions of power, have reached such diametrically opposed
conclusions?
One answer is that, while interested in distributions of power, neither theory sees
these as the sole determinants of international stability. The former introduces one
intervening variable – legitimacy – between material power and stability. The latter
injects an alternative variable – hegemony – that is again distinct from purely
distributional concepts. Despite the sharp disagreement between them as to their
respective preferences for dispersal or concentration of power, they in fact share a
highly significant common belief that stability is a function not simply of material
distributions, but also of the degree of shared values. It is this shared feature that
offers the prospect of a theory of international society – applicable to conditions of
primacy – combining the virtues of both legitimacy and hegemony.
The first cluster includes those political theorists who have long claimed a direct
correlation between legitimacy and stability. This is because legitimacy denotes an
acceptable, or authoritative, set of political conditions, and is less likely to meet
resistance, or to require maintenance by coercive or other means of inducement.
Such a view has been prevalent since Max Weber’s seminal discussion.^51
This relationship was imported into IR most famously via the work of Henry
Kissinger. ‘Stability’, he concluded, ‘has commonly resulted not from a quest for
peace but from a generally accepted legitimacy’.^52 Historically, that relationship was
demonstrated in the post-1815 period: ‘the period of stability which ensued was the
best proof that a “legitimate” order had been constructed’.^53 Kissinger’s ‘legitimacy’
was, of course, defined minimally as ‘an international agreement about the nature
of workable arrangements and about the permissible aims and methods of foreign
policy’, and as ‘the acceptance of the framework of the international order by all
major powers’.^54 This connection between legitimacy and stability has since been
further explored by various international historians and theorists.^55 On these views,
international stability derives from more than the material distribution of power
alone: the critical intervening variable is the attainment, or otherwise, of a shared
conception of international legitimacy.
The second cluster dwells instead upon hegemony as the most likely condition
for international stability, and HST is the best known of its sub-theories.^56 Most
famously, this has concentrated on stability in the international economic order, and
grew directly from Charles Kindleberger’s analysis of the causes of the Great
Depression.^57 However, by extension, it has been applied also to the wider political
How hierarchical can international society be? 277