International Law and International Relations

 International Law and International Relations

This volume is intended to help readers understand the relationship

between international law and international relations (IL/IR). The

excerpted articles, all of which were first published in International

Organization, represent some of the most important research since

serious social science scholarship began in this area more than twenty

years ago. The contributions have been selected to provide readers with

a range of theoretical perspectives, concepts, and heuristics that can be

used to analyze the relationship between international law and inter-

national relations. These articles also cover some of the main topics of

international affairs. In this brief preface, we note the rise of law in

interstate relations and flag some of the most important theoretical

approaches to understanding this development. We also introduce the

topics chosen and discuss the volume’s organization.

the rise of law in international relations

The study of international law has enjoyed something of a renaissance in

the last two decades. Of course, international affairs have long been

assumed to include international legal issues. Yet, in the first third of the

twentieth century, analysts did not sharply distinguish ‘‘international

law’’ from ‘‘international relations.’’ International relations courses were

often about international law and frequently confounded the prescripts of

international law with the way states were said to behave in fact. By the

time the United States entered the Second World War, that illusory

mistake was exposed: it was clear that international legal rules and

processes had not operated the way many had hoped. The failure to

contain German and Japanese aggression, the weakness of agreements

to keep the international economy functioning, and the humanitarian

disasters of the Second World War made most observers acutely aware of

the limits of law in international affairs. For more than thirty years after

the end of the war, American political science turned its back on

international law, focusing its study of international relations on the

material interests and observed behavior of states.

Yet by the early 1980s, many international relations scholars had

rediscovered a role for law in interstate relations. Reflecting on the post-

war order, many recognized that it was built not only upon power

relationships but also on explicitly negotiated agreements. These agree-

ments in themselves increasingly piqued scholarly interest. One reason

may have been the sheer proliferation of such agreements. A century ago,

most international law was said to arise from custom – evidenced by

continuous, recurrent state practice and opinion juris (i.e., the practice

was compelled by legal obligation). For a number of reasons – including

the growth of independent states, the lack of consent implied by many

approaches to customary law, the increasingly detailed nature of in-

ternational agreements, and the rise of multilateral treaty-making capac-

ity, e.g. by various working groups of the United Nations – today, many

(if not most) international legal obligations are expressed in treaty form.

Some treaties codify customary law, but in a way that respects the express

consent of the states that are parties to them.

Figure 1 shows the number of new multilateral treaties concluded 

in each quarter of the last century. While the number of new multilateral

treaties grew from 1900 to 1975 and then began to decline in the 1976–

95 period, Figure 1 strongly suggests that the aggregate number of

multilateral treaties in force has grown rapidly in the last hundred years.

Not only has the number of treaties grown, so has the scope of topics

and subjects addressed by treaty law. As Figure 1 suggests, treaty growth

has been especially marked in economic affairs, as well as in areas of

human welfare and the environment. Moreover, in the late nineteenth

century, most international law defined the rights and responsibilities of

states toward each other – purely ‘‘public’’ international law. Over the

course of the twentieth century, international law increasingly began to

address the responsibilities of states toward individuals and nonstate

actors (characteristic of human rights treaties), and set forth rules gov-

erning the relationships of private individuals and nonstate actors toward

each other – an expansion of private international law. This latter de-

velopment is reflected in such important treaties as the United Nations

Convention on the International Sale of Goods, which is essentially

a global commercial code, and the United Nations Convention on the

Recognition and Enforcement of Foreign Arbitral Awards, which has

enhanced the effectiveness of private international dispute settlement.

In this context, it is perhaps not surprising that the authority to

adjudicate international disputes has been delegated increasingly to

international courts. Figure 2 shows that the number of international

judicial, quasi-judicial, and dispute settlement bodies has grown from just

a handful in 1900 to nearly a hundred today. Moreover, the rate at which

dispute settlement bodies are growing has accelerated in the last 25 years.

Interstate disputes over territory, trade, human rights, environmental

protection, intellectual property, labor protection, and criminal matters

may now be resolved in international institutions that more or less re-

semble well-developed domestic legal systems in the way they apply legal

standards, procedures, and norms to dispute resolution. Some of these

institutions, such as the European Court of Justice (ECJ) and the World

Trade Organization’s (WTO) dispute settlement system, have compulsory

jurisdiction over member states or territories and enjoy impressive rates

of compliance with their decisions.

What explains the explosive growth of treaty law, the broader scope

of international law topics and subjects, and expansion of interna-

tional venues for law-based dispute resolution? Does international law

affect the behavior of individuals, states, and nonstate actors? How

Figure 1. Number of New Multilateral Treaties Concluded

does international law – and how do particular international rules and

procedures – affect interstate relations? These are some of the questions

addressed by social science and legal scholarship, of which the articles in

this volume are examples.

theories of law in international affairs

One way to understand the proliferation of legal arrangements is to view

them as an epiphenomenon of more basic relationships between states.

This is the position of scholars informed by structural realist theories: The

interests of powerful states determine the content of international

law, which in and of itself has little independent impact on behavior or

outcomes. In conceptualizing ‘‘international regimes,’’ Stephen Krasner’s

contribution in Part I of this volume sets forth this position in its pure

form (Krasner 1982). Another selection in this volume, by Downs, Rocke,

and Barsoom (1996), reflects similar skepticism about the extent to

which international law has autonomous explanatory power. Other

realist work, however, such as Steinberg (2002) and Garrett, Kelemen,

and Schulz (1998) in this volume, affords some important functions to

international law, while maintaining that law nonetheless reflects un-

derlying power. Number of bodies

Figure 2. Growth in International Judicial, Quasi-judicial, and

Quasi-judicial and other dispute settlement bodies Judicial bodies

If law does simply reflect underlying power relationships, this raises

the question of why states bother to create rules to order their inter-

actions at all. A rationalist institutionalist theory was offered in early

form by Robert Keohane (1982), an excerpt from which appears in Part I

of this volume. Using a rationalist logic that was built on the same assump-

tions employed by structural realism, Keohane showed that international

institutions could facilitate cooperative, positive sum outcomes that would

not otherwise occur. Keohane’s paradigmatic example was the prisoners

dilemma, which he (and others following him) argued was a metaphor for

much of international life. Rationalist argumentation that infuses legal

institutions with autonomous explanatory power has since been a main-

stay of much IL/IR literature. Increasingly, rationalist institutionalist

scholarship has shifted from questions about how international law

matters to questions about why legal forms vary (see, e.g., Lipson 1991,

in this volume) and why treaty design varies (see, e.g., Smith 2000 and

Koremenos 2001, both in this volume).

Much of the early rationalist work, whether realist or institutionalist,

has treated states as unitary actors with interests that are exogenous to

the argument. This evades a crucial question: where do interests come

from? Liberal theories offer an answer: ‘‘State interests’’ are best under-

stood as an aggregation and intermediation of individual and group

interests. International law in this view is driven from the bottom up. For

example, a selection from Andrew Moravcsik in this volume argues that

the European human rights regime expanded rapidly in the wake of the

Cold War, as nascent democracies that supported human rights pro-

tection emerged in Eastern Europe (Moravcsik 2000).

Liberalism may explain much of the content of international law, but

it affords little autonomous role to law; however, when liberal processes

are viewed as operating in the context of particular institutional arrange-

ments, law may be afforded a crucial explanatory role. For example,

Slaughter and Mattli’s contribution to this volume shows how the ECJ

offered a path for European interests that differed from the European

Community’s legislative path, reconfiguring European interests in ways

that reshaped outcomes (Slaughter and Mattli 1993). Similarly, Keohane,

Moravcsik, and Slaughter show how variance in the legal structure of

international dispute resolution may explain the extent to which the

various processes expand international law (Keohane, Moravcsik, and

Slaughter 2000). Other selections in this volume, such as Goldstein and

Martin (2000) and Gaubatz (1996), also combine liberal and institutional

elements to generate interesting explanations.

Influenced by postmodern social theory, constructivists delved even

more deeply into the question: Where do interests come from? Con-

structivists launched an ontological attack on the rationalist work that

preceded it, claiming that neither interests nor power exists independent

of the social context in which actors are enmeshed. Interests and identity

are constructed socially; they are plastic and may be redefined. Inter-

national law may be understood as both a reflection of identities and

as a social artifact that reinforces identities, interests, and power. Vari-

ations on this view are articulated by several selections in this volume,

including critiques of nonconstructivist approaches in Wendt (2001) and

Finnemore and Toope (2001) and arguments about the importance of

norms in shaping and understanding the operation of international law

by Jackson (1987), Legro (1997), and Zacher (2001).

contemporary research and the organization

of this volume

Increasingly, contemporary IL/IR research organizes less around abstract

theoretical debates and more around particular methods and concepts

that may be seen as hybrids of the main approaches. Increasingly, there is

conscious engagement across meta-theories, with a focus on mid-level

analysis of international legal and political developments using hybrid

theories and powerful methods to test those theories.

Part II of this volume is largely organized around these developments,

and newer heuristics and debates associated with them. This part high-

lights the distinction between making a commitment to an international

rule and compliance with it. Gaubatz (1996) introduces the ‘‘credible

commitment’’ concept (which suggests that a costly commitment by one

state may induce other states to behave differently from the way they

would otherwise behave) to the debate about treaty effects and suggests

that at least some treaty commitments by democracies may be more

credible than commitments by nondemocracies. Chayes and Chayes

(1993) present what has become known as the ‘‘managerial’’ theory of

treaty compliance, offering reasons that explain why states generally

comply with treaties. Downs, Rocke, and Barsoom (1996) offer a

skeptical counterpoint to Chayes and Chayes (1993) and others, arguing

that apparent state ‘‘compliance’’ frequently results from treaty provi-

sions that require little more than states would do in the absence of

treaties, and that in other cases compliance is usually explained by self-

interest or enforcement pressures from powerful states.

Part III explores the ‘‘legalization’’ of international relations, which

was the topic of a widely read IO special issue in 2000. The first contribu-

tion (Abbott et al. 2000) defines the concept of legalization. Keohane,

Moravcsik, and Slaughter (2000) argue that transnational adjudication

causes more expansive international law-making than interstate dispute

resolution. Goldstein and Martin (2000) offer reasons to be cautious

about concluding that legalization is normatively desirable. Finnemore

and Toope (2001) suggest that most of the work on ‘‘legalization’’ is

limited by its narrow definition and the associated ontological orienta-

tion, which prevents the concept from adequately accounting for the

reciprocal relationship between international law and social practice.

Part IV explores the relationship between international law and inter-

national norms. The first piece, by Robert Jackson (1987), argues that

competing definitions of sovereignty and statehood suggest that interna-

tional theory must accommodate morality and legality as autonomous

variables. Legro (1997) shows that some norms affect state behavior

more than others, and he identifies factors that influenced which norms

concerning the use of force mattered most in World War II. Zacher (2001)

suggests ideational and instrumental factors that influence the strength

of norms, examining the norm against coercive territorial revisionism.

Part V considers the growing literature on treaty design and dynamics.

Three of the selections (Lipson 1991, Smith 2000, and Koremenos 2001)

offer a rationalist explanation for a particular attribute of international

agreement design – why some international agreements are informal; why

the extent of legalism in dispute settlement mechanisms varies across

agreements; and why some agreements contain escape clauses or provide

for a short duration. Wendt (2001) offers a constructivist critique of the

rationalist approach to understanding treaty design, suggesting limits of

the approach. Diehl, Ku, and Zamora (2003) present a perspective

suggesting that international law can only be understood systemically

and dynamically, by considering how international law changes (or does

not change) as norms or other political factors change.

Part VI presents two competing views of the European Court of Justice

(ECJ), which is considered by many to be the world’s most legalized and

sophisticated international court. Slaughter [Burley] and Mattli (1993) is

a classic article, using neofunctionalist theory to argue how the authority

and independence of the ECJ have grown and how the court has played an

autonomous role in European integration. Garrett, Keleman, and Schulz

(1998) challenge this view, arguing that the ECJ is so constrained by

European politics that it should not be seen as a truly autonomous actor.

Part VII presents some classic articles that use IL/IR theory to un-

derstand particular substantive areas of international law. This includes

articles that explore the extent to which international agreements

maintain peace after conflict (Fortna 2003), how powerful countries

use ‘‘invisible weighting’’ to influence outcomes under ‘‘consensus-based’’

decision-making rules at the World Trade Organization (Steinberg 2002),

and why governments commit themselves to particular International

Monetary Fund rules and the conditions under which they comply with

those rules (Simmons 2000). Other selections consider the politics of

war crimes tribunals (Rudolph 2001), explain the surge of commitment

to human rights regimes in postwar Europe (Moravcsik 2000), identify

treaty features that favor compliance with the international oil pollu-

tion control regime (Mitchell 1994), and explore state behavior in the

‘‘regime complex’’ of overlapping treaties governing plant genetic re-

sources (Raustiala and Victor 2004).

conclusion

The scholarship linking international law and international relations

has developed significantly over the past three decades. International

Organization has published some of the most important research in this

area, and the articles reprinted here represent major theoretical and em-

pirical contributions. As a testament to this dynamic area of inquiry,

new research on IL/IR is now being published in a growing range of tra-

ditional law reviews and disciplinary journals. The articles reprinted

here were important milestones toward making IL/IR a central concern

of scholarly research in international affairs.

Beth A. Simmons Richard H. Steinberg

Cambridge, Massachusetts Los Angeles, California