Profound and rapid changes in the costs and risks of international trade are now widely acknowledged to be a potent source of domestic political conflict. By altering the relative prices of goods available from world markets, these changes alter the rewards that flow to different factors of production from different economic activities. These distributional consequences of changing levels of trade, in turn, alter the configuration of interests in the domestic political economy, strain existing political alignments, and enable the construction of new political coalitions. Thus, global changes in the economy, such as the transportation and telecommunications revolutions in the nineteenth and mid-twentieth centuries or the collapse of international trade and finance during the interwar years, will have global consequences as they reverberate within and through the domestic politics of all countries that trade on world markets.

How do domestic political institutions affect the way states interact in international crises? In the last decade we have witnessed an explosion of interest in this question, thanks largely to the well-known claim that democratic states do not fight wars with one another. Work on the “democratic peace” has generated a number of theoretical arguments about how practices, values, and institutions associated with democracy might generate distinctive outcomes. Although the level of interest in this topic has focused much-needed attention on the interaction between domestic and international politics, the proliferation of competing explanations for a single observation is not entirely desirable. Progress in this area requires that researchers devise tests not only to support different causal stories but also to discriminate between them.

Does informal intervention by high officials of international organizations decisively influence the outcomes of multilateral negotiations? In the words of two leading international lawyers, can “faceless international bureaucrats, unelected and without power of purse or sword” really influence the decisions of powerful nation-states? Are we seeing the emergence of a “new statecraft” grounded in international networks managed by supranational political entrepreneurs?

Although international relations scholarship emphasizing the role of social constructs such as norms and culture has established a beachhead in the area of security studies, it has yet to take on another bastion of the rational materialist approach: studies of coercive international bargaining. Scholarship in this area, ranging from the work of Thomas Schelling to James Fearon, has long argued that bargaining outcomes reflect the material costs and benefits faced by participants in negotiations. Participants can influence outcomes, these models assume, only through tactics such as credible threats and side payments that reshape the material context of negotiations.

Last year the U.S. Senate overwhelmingly approved the expansion of the Atlantic alliance. Whereas some advocates of enlarging NATO, particularly Eastern European leaders for whom the Soviets' iron grip is an all too recent memory, stress the extension of the alliance's traditional deterrent function, others acknowledge that Russia is in no position to reconquer its former empire. Rather, they argue that membership in NATO would stabilize the region by filling the power vacuum and eliminating the need for security competition. Traditionally a volatile area, East-Central Europe is rife with potential irredentist and ethnic conflicts, and NATO can help arbitrate and limit these disputes. Critics have denounced the move as unnecessarily provocative to Russia, and they have also decried its hefty cost. But they have not challenged the claim that alliances create zones of peace.

What motivates states to follow international norms, rules, and commitments? All social systems must confront what we might call the problem of social control—that is, how to get actors to comply with society's rules—but the problem is particularly acute for international relations, because the international social system does not possess an overarching center of political power to enforce rules. Yet, taken in balance with other values, a measure of order is a valued good. Some take this absence of centralized power to mean that the international system is like a Hobbesian state of nature, where only material power matters; others see it as evidence that international rules have force only when they are in the self-interest of each state. I show that these two conclusions are premature because of their shallow reading of international society and misinterpretation of the ways in which authority works in domestic society.

Analysts of the European Union (EU) and international bargaining have generally failed to appreciate how the shift within the EU from unanimity to qualified majority voting has affected European bargaining positions and international outcomes. I analyze the international effects of changes in EU decision-making rules with a simple spatial model and assess the utility of the model in two cases of environmental bargaining that span the entry into force of the Maastricht Treaty. The EU can decisively shape international outcomes by concentrating the weight of its fifteen member states on a single substantive position and rendering that position critical to any internationally negotiated agreement. The findings generalize to numerous areas of EU external relations and suggest that analysts should attend specifically to the EU and more generally to domestic and regional institutional factors in explaining international bargaining outcomes.