talk, realist thinking
and realism are the two bodies of theory which hold places of
privilege on the theoretical menu of international relations.
Most of the great intellectual battles among international relations
scholars take place either across the divide between realism and
liberalism, or within those paradigms.
liberal tradition has its roots in the Enlightenment, that period
in 18th-century Europe when intellectuals and political leaders
had a powerful sense that reason could be employed to make the
world a better place. Accordingly, liberals tend to be hopeful
about the prospects of making the world safer and more peaceful.
Most liberals believe that it is possible to substantially reduce
the scourge of war and to increase international prosperity. For
this reason, liberal theories are sometimes labeled "utopian"
optimistic view of international politics is based on three core
beliefs, which are common to almost all of the theories in the
paradigm. First, liberals consider states to be the main actors
in international politics. Second, they emphasize that the internal
characteristics of states vary considerably, and that these differences
have profound effects on state behavior. Furthermore, liberal
theorists often believe that some internal arrangements (e.g.,
democracy) are inherently preferable to others (e.g., dictatorship).
For liberals, therefore, there are "good" and "bad"
states in the international system. Good states pursue cooperative
policies and hardly ever start wars on their own, whereas bad
states cause conflicts with other states and are prone to use
force to get their way. Thus, the key to peace is to populate
the world with good states.
liberals believe that calculations about power matter little for
explaining the behavior of good states. Other kinds of political
and economic calculations matter more, although the form of those
calculations varies from theory to theory. Bad states might be
motivated by the desire to gain power at the expense of other
states, but that is only because they are misguided. In an ideal
world, where there are only good states, power would be largely
contrast to liberals, realists are pessimists when it comes to
international politics. Realists agree that creating a peaceful
world would be desirable, but they see no easy way to escape the
harsh world of security competition and war. Creating a peaceful
world is surely an attractive idea, but it is not a practical
one. "Realism," as E. H. Carr notes, "tends to
emphasize the irresistible strength of existing forces and the
inevitable character of existing tendencies, and to insist that
the highest wisdom lies in accepting, and adapting oneself to
these forces and these tendencies."
gloomy view of international relations is based on three core
beliefs. First, realists, like liberals, treat states as the principal
actors in world politics. Realists focus mainly on great powers,
however, because these states dominate and shape international
politics and they also cause the deadliest wars. Second, realists
believe that the behavior of great powers is influenced mainly
by their external environment, not by their internal characteristics.
The structure of the international system, which all states must
deal with, largely shapes their foreign policies. Realists tend
not to draw sharp distinctions between "good" and "bad"
states, because all great powers act according to the same logic
regardless of their culture, political system, or who runs the
government. It is therefore difficult to discriminate among states,
save for differences in relative power. In essence, great powers
are like billiard balls that vary only in size.
realists hold that calculations about power dominate states' thinking,
and that states compete for power among themselves. That competition
sometimes necessitates going to war, which is considered an acceptable
instrument of statecraft. To quote Carl von Clausewitz, the 19th-century
military strategist, war is a continuation of politics by other
means. Finally, a zero-sum quality characterizes that competition,
sometimes making it intense and unforgiving. States may cooperate
with each other on occasion, but at root they have conflicting
there are many realist theories dealing with different aspects
of power, two of them stand above the others: human nature realism,
which is laid out in Hans Morgenthau's Politics among Nations
(1948), and defensive realism, which is primarily presented in
Kenneth Waltz's Theory of International Politics (1979).
What sets these works apart from those of other realists and makes
them both important and controversial is that they explain why
states pursue power-that is, they have a story to tell about the
causes of security competition-and each offers an argument about
how much power a state is likely to want.
nature realism, which is sometimes called "classical realism,"
dominated the study of international relations from the late 1940s,
when the writings of Morgenthau (who taught at Chicago) began
attracting a large audience, until the early 1970s. It is based
on the simple assumption that states are led by human beings who
have a "will to power" hardwired into them at birth.
That is, states have an insatiable appetite for power, or what
Morgenthau calls a "limitless lust for power," which
means that they constantly look for opportunities to take the
offensive and dominate other states. All states come with an "animus
dominandi," so there is no basis for discriminating among
more aggressive and less aggressive states, and there certainly
should be no room in the theory for status quo states. Human nature
realists recognize that international anarchy-the absence of a
governing authority over the great powers-causes states to worry
about the balance of power. But that structural constraint is
treated as a second-order cause of state behavior. The principal
driving force in international politics is the will to power inherent
in every state in the system, and it pushes them to strive for
realism, which is frequently referred to as "structural realism,"
came on the scene in the late 1970s with the appearance of Waltz's
Theory of International Politics. Unlike Morgenthau, Waltz
does not assume that great powers are inherently aggressive because
they are infused with a will to power; instead he starts by assuming
that states merely aim to survive. Above all else, they seek security.
Nevertheless, he maintains that the structure of the international
system forces great powers to pay careful attention to the balance
of power. In particular, anarchy forces security-seeking states
to compete with each other for power, because power is the best
means to survival. Whereas human nature is the deep cause of security
competition in Morgenthau's theory, anarchy plays that role in
does not emphasize, however, that the international system provides
great powers with good reasons to act offensively to gain power.
Instead, he appears to make the opposite case: that anarchy encourages
states to behave defensively and to maintain rather than upset
the balance of power. "The first concern of states,"
he writes, is "to maintain their position in the system."
There seems to be, as international relations theorist Randall
Schweller notes, "a status quo bias" in Waltz's theory.
recognizes that states have incentives to gain power at their
rivals' expense and that it makes good strategic sense to act
on that motive when the time is right. But he does not develop
that line of argument in any detail. On the contrary, he emphasizes
that when great powers behave aggressively, the potential victims
usually balance against the aggressor and thwart its efforts to
gain power. For Waltz, in short, balancing checkmates offense.
Furthermore, he stresses that great powers must be careful not
to acquire too much power, because "excessive strength"
is likely to cause other states to join forces against them, thereby
leaving them worse off than they would have been had they refrained
from seeking additional increments of power.
views on the causes of war further reflect his theory's status
quo bias. There are no profound or deep causes of war in his theory.
In particular, he does not suggest that there might be important
benefits to be gained from war. In fact, he says little about
the causes of war, other than to argue that wars are largely the
result of uncertainty and miscalculation. In other words, if states
knew better, they would not start wars.
with defensive realism, my theory-offensive realism-sees great
powers as concerned mainly with figuring out how to survive in
a world where there is no agency to protect them from each other;
they quickly realize that power is the key to their survival.
Offensive realism parts company with defensive realism over the
question of how much power states want. For defensive realists,
the international structure provides states with little incentive
to seek additional increments of power; instead it pushes them
to maintain the existing balance of power. Preserving power, rather
than increasing it, is the main goal of states. Offensive realists,
on the other hand, believe that status quo powers are rarely found
in world politics, because the international system creates powerful
incentives for states to look for opportunities to gain power
at the expense of rivals, and to take advantage of those situations
when the benefits outweigh the costs. A state's ultimate goal
is to be the hegemon in the system.
should be apparent that both offensive realism and human nature
realism portray great powers as relentlessly seeking power. The
key difference between the two perspectives is that offensive
realists reject Morgenthau's claim that states are naturally endowed
with Type A personalities. On the contrary, they believe that
the international system forces great powers to maximize their
relative power because that is the optimal way to maximize their
security. In other words, survival mandates aggressive behavior.
Great powers behave aggressively not because they want to or because
they possess some inner drive to dominate, but because they have
to seek more power if they want to maximize their odds of survival.
the best brief for offensive realism is a short, obscure book
written during World War I by G. Lowes Dickinson, a British academic
who was an early advocate of the League of Nations. In The European
Anarchy, he argues that the root cause of World War I "was
not Germany nor any other power. The real culprit was the European
anarchy," which created powerful incentives for states "to
acquire supremacy over the others for motives at once of security