22 International Relations Theory of War
with a distinction between the three possible polarity models that have
taken place in the subject period of the study, 1816–2016: multipolar, bipo-
lar, and unipolar systems, in each of the six instances that are discussed
below. The quantitative assessment is undertaken by examining all wars
between countries in the three models: central wars, major wars, and
minor wars, in which the polar powers constituting the system have been
involved.
By definition, territorial expansion occurs when one or more of the fol-
lowing six options occur at the end of a war: conquest, annexation, ces-
sion, secession, unification, or mandated territory.^26
Conquest is territorial expansion that fulfills five conditions simultane-
ously:^27 (1) the conquest is achieved by war, (2) the main territorial change
agent is military force, (3) military forces of one nation seize part or all
of the territory of another nation,^28 (4) the conquered territory is under
the authority of the conquering military either directly using its military
forces or indirectly using local military forces that answer to the occupy-
ing military, and (5) the conquering state’s control over the territory of the
conquered state is temporary and does not claim rights of permanent sov-
ereign control of that territory. Territorial expansion will not be considered
as conquest primarily in the case of wartime occupation^29 because it may
differ from the final territorial result of the war, which may involve with-
drawal or territorial contraction of the occupying power; secondly, in the
case of UN presence (UN forces are usually welcomed by the conquered
population, and the multinational character of the occupation reduces the
pressure on the occupying powers to end the occupation); thirdly, in the
case of short-term involvement in which the occupying power exerts lim-
ited political influence on the territory in which it has intervened. There-
fore, short-term involvements of polar powers in other countries, such as
the U.S. involvement in the Dominican Republic (1965), Panama (1983),
and Haiti (1994),^30 are not considered conquests.^31
Annexation means acquisition of territory belonging to another country,
or not belonging to any country, and permanent unification with the ter-
ritory of that annexing country. This is usually a unilateral action whose
key change agent is diplomacy, even if it involves an implicit threat of use
of force. This action includes application of full sovereignty by the new
controller and applying an exclusive judicial and control system to the
territory. Annexation differs from military occupation, although military
occupation may stem from it.^32
Cession occurs when part of a political entity is given to another political
entity through a referendum, purchase,^33 or compensation agreement, or
following hostility.
Secession or withdrawal from territories refers to detachment from an exist-
ing border to the existence of another entity living in it for that entity to
form a new independent entity.