The democratic and territorial peace arguments explain interstate peace via distinct mechanisms. Yet they can be integrated. I theoretically derive both the unique domains in which each argument might operate and the ways in which the two arguments might reinforce one another. An analysis of the period 1816–2001 demonstrates support for a more integrative approach. Within contiguous dyads, border settlement significantly reduces conflict, even for non-democratic dyads. Democratic dyads, however, experience no such effect in the absence of border settlement. Nonetheless, the democratic peace functions strongly in non-contiguous dyads, and even the most peaceful, contiguous dyads require both democracy and border settlement. Such findings offer a foundation for further theoretical development that integrates the two arguments.
The steps-to-war theory maintains that war results from the issues under dispute and how states handle these issues. Its foundation rests on the territorial explanation of war, which argues that territorial issues are more conflict-prone than non-territorial ones because these issues constitute a salient security threat that realism recommends be addressed via power politics (i.e., the use of force, including alliance- and armament-building). When states employ power politics, however, the dispute festers, thereby causing recurring militarized conflict; creating feelings of threat, enmity, and competition (i.e., rivalry); producing counter-alliances and arms races; and generally building the more hostile, war-prone world that states originally sought to avoid. Each step taken—from a territorial dispute to rivalry (i.e., recurring militarized disputes) to alliance-building to armament building—therefore increases the probability that war will occur.Existing empirical evidence supports the steps-to-war theory's predictions in numerous ways. Tests of the entire theory, for example, demonstrate the dangerousness of territorial disputes, the tendency to manage territorial disputes via power politics, and that individual steps reinforce one another. Other bodies of research connect the individual steps directly to the likelihood that war will occur or highlight the connections between these individual steps—much as the theory predicts. Despite strong empirical support, however, much work remains to be done. Future research should consider the sequencing of the steps to war, investigate why the effects of certain steps vary across different epochs (e.g., alliances differ in their effects on war during the 18th and 19th centuries), identify the alternative paths to war, and study the paths to peace more explicitly—as obtaining peace may not be as simple as removing the known causes of war.
Do democratic dyads handle their disputes more peacefully than non-democratic dyads, or have they cleared the most contentious issues (that is, unsettled borders) off their foreign policy agenda before becoming democratic? This study compares the conflicting answers of the democratic peace and the territorial peace and examines the empirical record to see which is more accurate. It finds that almost all contiguous dyads settle their borders before they become joint democracies. Furthermore, the majority of non-contiguous dyad members also settle their borders with all neighboring states before their non-contiguous dyad becomes jointly democratic. Such findings are consistent with the theoretical expectations of the territorial peace, rather than the democratic peace. They also weaken a core argument of the democratic peace, for this analysis finds that one reason democratic dyads may handle their disputes more peacefully than non-democratic dyads is not because of their institutions or norms, but rather because they have dispensed with the disputes most likely to involve the use of military force prior to becoming democratic.
There is increasing evidence that territorial conflict is associated with centralized and nondemocratic regimes. We explore whether this relationship is due to the facility of democratic regimes to settle their international borders. Using Owsiak's data set on border settlement processes, we find little evidence that democratic regimes are more likely than other types of regimes to settle their borders. In fact, joint democracy rarely precedes the first border agreement or full settlement of the border, and there is almost no qualitative evidence suggesting a link between democracy and border settlement in the rare instances of successful agreements. Democracies are also not more likely to keep their borders settled or even to be more peaceful during settled-border years. Overall, our findings suggest that border settlements lead to peace in the dyad and affirm a clear temporal sequence of border settlement, then peace and democracy for neighboring dyads.
Why do disputants favor some conflict management strategies when managing certain territorial claim types—land, river, or maritime—but not others? We propose that state interests—defined via claim characteristics and interdependence—and transaction costs (i.e., the challenges associated with aggregating state preferences over outcomes) differ across claim types. These differences then incentivize states to cede varying levels of control over claim management, ultimately encouraging them to prioritize and institutionalize certain conflict management strategies when managing particular types of territorial claims. More specifically, we theorize and find that states pursue distinct management strategies when addressing their land (informal; bilateral negotiations and arbitration), river (more formal; third-party non-binding), and maritime claims (most formal; multilateral negotiations and legal processes).