Introduction: International Relations Theory of War 5
study at the end of 2016 but may persist into the future)—has been discov-
ered to be more stable than multipolarity and less stable than bipolarity.^7
THE INTRASYSTEMIC INTERNATIONAL OUTCOMES—
TERRITORIAL EXPANSION OF POLAR POWERS
The second family of international outcomes that the theory assesses
includes intrasystemic international outcome, or the degree of territorial
expansion by polar powers at the end of the wars in which they have par-
ticipated; this family is assessed in studies dealing with the causes of the
outcomes of wars. The theory defines territorial expansion as occurring
when one of the following six options applies, as long as they occur at the
end of the war rather than while it is still being fought: conquest, annexa-
tion, cession, secession, unification, or mandated territory.
The theory defines the degree of territorial expansion by polar powers
at the end of wars in which they have participated through three values:
territorial expansion, territorial contraction, or territorial status quo ante
bellum.
The conclusion arising from the theory is that unipolar systems will
dictate the territorial expansion of the sole hyperpower; bipolar systems
will lead to a territorial status quo ante bellum of the two superpowers;
and multipolar systems, alternatively, will dictate territorial nonexpansion
(status quo ante bellum or territorial contraction) or will allow territorial
expansion of the great powers.
The conclusions of the book concerning the degree of territorial expan-
sion of the polar powers at the end of the wars in which they fought
correspond with its basic assumptions. In all three instances of bipolarity—
1816–1848, 1871–1909, and 1946–1991—all wars involving the polar pow-
ers, or the two superpowers that constituted each of the instances, ended
with a territorial status quo ante bellum. In the single instance of unipolar-
ity, in 1992–2016, all wars in which the polar power—the sole hyperpower
constituting that instance—was involved, ended with territorial expan-
sion of the hyperpower. In the two instances of multipolarity—1849–
and 1910–1945—two different territorial outcomes of the polar powers,
or the great powers constituting the system, at the end of the wars were
yielded. When the territorial outcome of expansion of the great power
would not have the potential for positioning the expanding power as a
hegemon in the system, the system permitted the expansion of the great
power at the end of the war. When the territorial outcome of the expan-
sion of the great power had the potential of positioning the expanding
power as a hegemon in the system, the system prevented the expansion
of the great power at the end of the war and eventually forced the reduc-
tion of the war.