What is the relationship between oil and international conflict? In an era of increased dependence on, and greater volatility within, global markets for oil and energy, this question is central to understanding contemporary world politics. It is an empirical fact that petrostates—defined as states that have at least 10% of GDP derived from oil exports—are more prone to international conflict than non-petrostates. Indeed, in the period 1965–2001, petrostates engaged in militarized interstate disputes at roughly twice the rate of non-petrostates, on average. What explains this propensity?

Scholarly work can be divided according to three different concepts of “resource war” that are often conflated. The first is what might be called resource conflict, which describes violent intrastate conflicts, such as civil wars, caused or exacerbated by oil or natural resources. A large and growing body of scholarly literature provides evidence that resource-exporting states are more likely to experience civil war than non-resource exporting states (Collier and Hoeffler Reference Collier and Hoeffler2004; Fearon and Laitin Reference Fearon and Laitin2003). Yet this literature does not speak directly to the question of international conflicts. The second body of work focuses on resource competition, which describes international conflicts based on the pursuit of scarce resources. Scholars have argued that increasing global demand for energy makes the conquest of major oil-exporting regions likely (Westing Reference Westing1986; Klare Reference Klare1999, Reference Klare2001). Yet as skeptics have pointed out, there is little systematic evidence available in support of this claim (Victor Reference Victor2007). In the postwar era, competition over resources has been managed largely by international markets rather than war between states. The view of petrostates as passive targets of conquest also gives rise to a problematic question: why is it that so many petrostates aggressively initiate conflicts?

This gives rise to the third, still developing body of work on resource-backed aggression. Iraq, Libya, Venezuela, and Russia have often been instigators of international conflict, rather than targets of resource conquest. On this view of the resource curse, large natural resources can be converted into military and political assets in support of aggressive foreign policy. In part this is due to the military expenditures made possible by oil income. However, clearly not all petrostates are aggressive in their foreign policy. Kuwait has a population roughly equal to Libya's, with at least as much oil and military hardware, yet it has generally behaved far less aggressively than Libya. A robust theory would be able to specify the conditions under which oil is used as an instrument of military aggression.

My research to date suggests that when revolutionary governments come to power in petrostates, they have an unusually high propensity to engage in international conflict compared to comparable non-petrostates. In general, oil appears to have two effects, one conflict enhancing (by reducing the leader's risk of domestic punishment for foreign policy adventurism and increasing the state's military capacity) and one conflict reducing (by increasing the economic incentives for peaceful international trade and stability in the global oil-export market). These two effects have a theoretically ambiguous impact on the behavior of non-revolutionary petrostates, but appear to have a consistently amplifying impact on the conflict propensity of revolutionary states. Thus petro-revolutionary states are more likely to engage in international conflict than comparable non-petrostates.

The interaction of oil income and revolutionary governments can be observed in petrostates from Libya to Venezuela. Indeed, the rise of president Hugo Chavez has some striking similarities with the career of colonel Muammar Qadhafi. Each of them came to power in the midst of national turmoil and discontent, in part by stoking popular outrage at the corruption in their petroleum-dependent countries. They promised to eliminate corruption and share the spoils of the state's oil income, but instead each has perpetuated and even deepened the corruption and national economic mismanagement. Both men spent lavishly on foreign policy goals and military hardware. At home, these men are ruthless and disinclined to share power; former friends and supporters are often removed, forgotten, or punished. Yet as leaders, they both have remarkable charisma and oratorical gifts; both crave attention and affirmation not only from their countrymen but from the world at large. They both take pride in having survived the condemnation of the United States, including when—perhaps especially when—they legitimately feared for their lives. For better and for worse, their countries are blessed with the one critical strategic resource that facilitates their political strategies and ensure they get the attention of countries all over the world: oil.

Understanding the domestic and international politics of petrostates is crucial as oil and energy become an increasingly important part of the global economy. As our scholarly work advances, we can hope to improve not only our understanding of the politics in petrostates, but also how best to tailor policy responses to their distinguishing problems and opportunities.