Abstract
Douglas M. Gibler cannot be accused of setting his sights low in The Territorial Peace: Borders, State Development, and International Conflict. Indeed, the book’s thesis is decidedly bold. Gibler argues that disputes over territory cause both state centralization and enduring conflicts. Conversely, states that enjoy a “territorial peace” in which their homeland is infrequently targeted and their borders are stable will experience more democracy and more peace with neighbors. For Gibler, democracy and peace coexist, but their connection is spurious; both are an offshoot of a territorial peace. Thus, Gibler purports to explain both democracy within states and the democratic peace between them with the same crucial variable. This is a monumental undertaking that contributes to two separate and enormous literatures. While Gibler’s argument is not always perfectly convincing—and I detail some of these shortcomings below—it does not lack for ambition.
The first part of the book lays out the theoretical foundations. In particular, Gibler wants to convince us that territorial disputes are different from other types of disputes, such as those regarding policy or regime change. Territorial issues “trigger multiple biological and psychological responses by individuals in threatened states” (p. 26). In various ways, individuals are likely to see their own survival as closely linked to the defense of territory, leading them to use (and approve of the use of) violence to stave off territorial threats. Threats to regime or disputes over policy do not draw the same reaction.
From this key insight about individual responses to territorial threats, the rest of the book unfolds as a series of important implications, beginning with state development. Territorial threats cause a rally effect as individuals put security first and display less tolerance for minority opinions (chap. 4). Threats to the homeland also compel leaders to increase the size of the military by creating or augmenting a large, standing army in a short period of time; having a large army increases chances of repression as elites wield the army to put down political opponents (chap. 5). Opposition parties that escape straightforward repression have incentives to rally to the side in power during territorial disputes, while executives can proactively exploit the situation by removing institutional impediments to authority (chap. 6). All arrows leading from territorial threats point in the same direction regarding state development: toward greater centralization of power and away from democratic governance.
Chapter 7 contains the crux of Gibler’s argument. First, he shows that his assortment of proxies for stable borders (peaceful territorial transfers, civil war onset in one member of the dyad, etc.) predict joint democracy, a measure that combines democracy scores for a given dyad. Second, he shows that those same measures lead to fewer fatal militarized disputes. In the latter, joint democracy is statistically significant in conflict-predicting regressions without the stable borders proxies but loses significance once the proxies are added. This suggests that what democratic peace theorists believed to be a separate democratic peace was really just a case of omitted variable bias; once stable borders variables are added, the famous link between democracy and peace disappears. Furthermore, settled borders free up states to opt for more negotiated settlements (chap. 8) and select into only those wars that they have a decent chance of winning (chap. 9). Again in these two implications, settled borders variables are displacing regime-based ones, and Gibler’s territorial peace is encroaching on the typical turf of democratic peace theory.
Gibler chooses conventional statistical methods to make his case, and he has at least one round of regression for each of his empirical chapters (4-9). He relies heavily on standard measures such as the Militarized Interstate Dispute variables from the Correlates of War project and Polity IV for regime type. Sometimes Gibler complies with the emerging norm of reporting substantive results, not just significance, and where he does this, it is helpful in assessing his claims. For instance, it is easier to believe that territorial threats are likely to lead to considerable increases in military personnel when we see that, holding other factors at their mean, states that are threatened in this way add an average of 114,771 military personnel during the course of a yearlong territorial dispute, versus only 270 soldiers for nonterritorial disputes (p. 80). Gibler does not maintain this approach for every chapter, unfortunately. For example, we cannot tell how much his stable border proxies impact the risk of a militarized dispute with fatalities from his table in chapter 7. Instead, we are given a smattering of nonlinear coefficients and significance stars which explain too little at best and mislead at worst.
Gibler’s most important contribution is his presentation of a cohesive theory with so much potential. Some previous contributions discussing neighborhoods of peace and democracy have been a bit light on theoretical reasons for why democracies cluster and why certain neighborhoods have formed. The democratic peace literature has also lacked agreement and clarity on what exactly connects democracy with peace. Gibler improves on these previous efforts. Each step of his argument strikes one as almost obvious. Threats to the homeland result in greater centralization of power? Of course. A standing army is needed to defend the homeland but can then be used for domestic repression? Sure. And so on. Yet each baby step brings us closer to believing Gibler’s main thesis, which is not obvious at all. This is theorizing at its best: convincing readers with small, plausible, logical connections until something new appears that we did not see before.
Any argument claiming that some factors cause democracy by showing their concurrence must take care to avoid the problem of endogeneity: How do we know that democracy was not the cause, rather than the effect, of stable borders? Gibler is aware of the problem, and he believes that he has at least a partial solution: using geographic features. Clearly, the democratic regimes of two states do not cause the river-based border they share, but using a river as a border, because it can serve as a focal point, might help in coordinating boundary negotiations. This can result in stable borders, which in turn can lead to greater tolerance of minority opinions, smaller land armies, less repression, and so on, until democracy is reached. Such an approach would be an effective way of avoiding the problem of endogeneity, but Gibler does not use focal point measures directly. Instead, he uses proxies, many of which do not have the benefit of being exogenous beyond doubt. For instance, a lack of civil war in a dyad might cause border stability, which leads to a more democratic regime. However, democracies are probably less likely to experience civil wars, because domestic interests presumably can find a nonviolent outlet for grievances and wishes. The fact that the civil war variable is lagged 1 year does little to ameliorate the problem; a democracy today is less likely to have had a civil war last year because it was probably a democracy then, too. Some of the other proxy variables are better—democracy, or lack thereof, does not cause a dyad to share the same historical colonial master, to take an example of another proxy variable for unstable borders—but overall, Gibler has a long way to go to placate concerns of reverse causality.
When the statistics fail to inspire, there is no case study—and worse, a dearth of illustrations—to step in and clarify matters. Relying solely on statistics for testing is acceptable; one cannot be expected to do everything, and this book already does many things in limited space. The lack of even empirical examples presents more of a problem. Not only do examples make the argument “real” for the reader by fleshing out the bare bones of theoretical language and statistical tables, but they also facilitate communication of Gibler’s ideas to a wider audience. In addition, examples help to clarify Gibler’s position in certain debates. One has to call history’s countries by name in order, say, to engage one of the liberal peace theorists’ central pieces of evidence: the peaceful transfer of hegemony (an issue that, like territorial disputes, has proven to be quite conflict-prone) from Britain to the United States in the 20th century (Doyle, 1983). To statistics, this is a mere data point; to history, it is a crucial event. Regions could also use more discussion. For instance, Jeffrey Herbst (1990) argues that Africa’s border stability and lack of transnational conflict since independence have made state consolidation difficult, resulting in weak authoritarian governments, a combination that sits uneasily with Gibler’s argument. Gibler might have good responses to these challenges, but he would have to delve a bit more into the debates of political history to produce them.
Perhaps this suggests a good next step for those interested in the territorial peace: to present a revision of political history in light of Gibler’s ambitious argument, with this book’s theorizing and statistical testing as a foundation.