chapter six:The Changing Nature of Military
Alliances
Contained in this two-volume collection are descriptions of
more than 450 alliances, spanning more than 350 years. Even
the most casual reader will realize that alliances have changed
greatly over time. Initially, most alliances were simple tools for
coordination. Two kings promised aid to each other in case of
attack, and the treaty text provided details of coordination,
stipulating the number of troops and how they would be fed,
sheltered, and equipped. These rather basic coordination agree-
ments slowly gave way to the more provocative use of alliances
as tools for influencing the policies of other nonallied states.
Although the structure of coordination between alliance part-
ners remained well-defined in these treaties, leaders also began
incorporating into the agreements the ideas of mutual interests
and aggressive bargaining with other states.
By the beginning of the nineteenth century, aggressive sig-
naling had become the norm for alliance agreements. Differ-
ent types of alliances were slowly emerging as tools for man-
aging conflict. These agreements focused on internal
rebellions or pledged neutrality in case of attack. Other
alliance types served to recognize new leaders and states, and
probably the most common of the conflict management
alliances were the agreements to settle the terms of control
over disputed territories.
The evolution of alliance making took another turn after
World War II, as both the United States and the Soviet Union
began defining their spheres of influence around the globe.
With these mostly bilateral alliances, the superpowers pledged
defense of their partners in exchange for basing rights, access to
ports and resources, and other similar goods. Large regional
organizations such as the Organization of American States
(OAS), the North Atlantic Treaty Organization (NATO), and
the Western European Union (WEU) were also formed, at least
in part, to influence and protect Western alliance partners.
These large regional organizations also inspired the creation of
other regional groupings such as the African Union and the
League of Arab States, which were dedicated to internal security
and trade. Gradually, the original anticommunist alliances also
evolved to primarily manage intra-alliance conflict, trade, and
other issues. In fact, the evolution of NATO, the OAS, and like
institutions had become so complete that there was no call to
disband these alliances after the Soviet Union dissolved. These
institutions were instead repurposed as tools for managing the
so-called new world order.
This conclusion to the two volumes describing alliances
since 1648 presents two significant trends in the evolution of
alliance making. The first trend concerns the globalization of
alliances. Having begun mostly in Europe, alliances are now
common tools for leaders around the globe. The second trend,
presented in the second section below, discusses how the pur-
poses of alliances can change with time: first, how alliance goals
have changed, and then how institutions such as NATO and the
OAS have been transformed.Globalization of Alliances
Perhaps the best way of describing just how pervasive in the
international system alliances have become is to point to the
number of states that are actually in an alliance in any given
year. Figure 1 charts the number of dyads (or pairs of states) in
the international system for each year since 1816. The concept
of a dyad is useful when describing alliance relationships
because it takes at least two states to form an alliance. In 1816,
for example, there were 23 states in the international system
according to the Correlates of War project; these 23 states could
combine in 226 different dyads. By 1900 there were 42 states
and 666 dyads, by 1945 there were 66 states and 840 dyads, and
by 2000 there were 191 states and 3,132 different dyads in the
international system.
The other two lines in Figure 1 show the percentage of dyads
that were in at least one alliance in any given year. In 1816, more
than half (55 percent) of the mostly European international
system was allied. The number of alliances remained steady
through the nineteenth century, but the number of dyads in the
international system began to increase as states in the Western
Hemisphere, Asia, and the Middle East became independent.
Thus, the percentage of allied dyads slowly decreased through-
out the century.