How the Research Is Empirically Examined 73
In the current chapter, I shall assess the international relations theory of
war empirically through examining the two dependent variables that the
theory assesses and based on the principles of the study described above.
The check is done by empirically examining the two international out-
comes that the theory is attempting to explain in 1816–2016. In the first
part, the systemic international outcome, the stability of the three possible
international system models is empirically assessed. In the second part,
the intrasystemic international outcome, the degree of territorial expan-
sion of polar powers at the end of wars that they have fought is assessed.
Systemic Factors and the Stability of Bipolar Systems
INTERNATIONAL SYSTEMS
Over the course of human history, some periods have been more stable
than others. Comparing the following two periods reveals significant dif-
ferences between European wars in terms of number of deaths: 1,858,000
in 1715–1792 compared with 635,000 in 1815–1914.^14 Similarly, a long-term
examination of the system of European countries reveals that war periods
were followed by periods of peace, and vice versa. For most of the 17th
and 18th centuries, war in Europe was at low ebb. In the 19th century,
there were longer periods of peace, but a number of wars and major crises
still occurred during it. At the beginning of the century, the long, bloody
Napoleonic Wars were fought. The Crimean War occurred in its middle,
and in its last third were the Wars of the Union of Italy and Germany. Both
World Wars, which occurred in the first half of the 20th century, continued
that pattern. Security competition is therefore inherent to the international
system, but war is not, because only in certain cases does security competi-
tion lead to war.
Because war is one of the most important and influential phenomena
facing humankind, many theories deal with examining the causes that
lead to the outbreak of wars. Some of these theories have pointed at human
nature as the cause of conflict and war. Other theories have pointed at
leaders, local politics, or the international system. Like the international
relations theory of war, a number of other theories indicate the division of
power as a factor that may explain conflicts in the international scene.
Waltz argues bipolar systems will be stable compared with multipolar
systems.^15 Mearsheimer states that bipolar systems will be the most stable,
unbalanced multipolar systems will be the most war-inclined, and bal-
anced multipolar systems will lie between them.^16 Unlike these theories,
which offer an explanation for just two of the three possible system mod-
els, the international relations theory of war offers its assumptions concerning
all three possible models—multipolar, bipolar, and unipolar systems.
As a structural theory, the international relations theory of war may assume
that international anarchy is the main systemic factor that leads countries