Iraq, Syria, Nigeria, South Sudan, Ukraine, the East and South China Seas: wherever you look, the world is aflame with new or intensifying conflicts. At first glance, these upheavals appear to be independent events, driven by their own unique and idiosyncratic circumstances. But look more closely and they share several key characteristics — notably, a witch’s brew of ethnic, religious, and national antagonisms that have been stirred to the boiling point by a fixation on energy.

In each of these conflicts, the fighting is driven in large part by the eruption of long-standing historic antagonisms among neighboring (often intermingled) tribes, sects, and peoples. In Iraq and Syria, it is a clash among Sunnis, Shiites, Kurds, Turkmen, and others; in Nigeria, among Muslims, Christians, and assorted tribal groupings; in South Sudan, between the Dinka and Nuer; in Ukraine, between Ukrainian loyalists and Russian-speakers aligned with Moscow; in the East and South China Sea, among the Chinese, Japanese, Vietnamese, Filipinos, and others. It would be easy to attribute all this to age-old hatreds, as suggested by many analysts; but while such hostilities do help drive these conflicts, they are fueled by a most modern impulse as well: the desire to control valuable oil and natural gas assets. Make no mistake about it, these are twenty-first-century energy wars.

It should surprise no one that energy plays such a significant role in these conflicts. Oil and gas are, after all, the world’s most important and valuable commodities and constitute a major source of income for the governments and corporations that control their production and distribution. Indeed, the governments of Iraq, Nigeria, Russia, South Sudan, and Syria derive the great bulk of their revenues from oil sales, while the major energy firms (many state-owned) exercise immense power in these and the other countries involved. Whoever controls these states, or the oil- and gas-producing areas within them, also controls the collection and allocation of crucial revenues. Despite the patina of historical enmities, many of these conflicts, then, are really struggles for control over the principal source of national income.

Moreover, we live in an energy-centric world where control over oil and gas resources (and their means of delivery) translates into geopolitical clout for some and economic vulnerability for others. Because so many countries are dependent on energy imports, nations with surpluses to export — including Iraq, Nigeria, Russia, and South Sudan — often exercise disproportionate influence on the world stage. What happens in these countries sometimes matters as much to the rest of us as to the people living in them, and so the risk of external involvement in their conflicts — whether in the form of direct intervention, arms transfers, the sending in of military advisers, or economic assistance — is greater than almost anywhere else.

The struggle over energy resources has been a conspicuous factor in many recent conflicts, including the Iran-Iraq War of 1980-1988, the Gulf War of 1990-1991, and the Sudanese Civil War of 1983-2005. On first glance, the fossil-fuel factor in the most recent outbreaks of tension and fighting may seem less evident. But look more closely and you’ll see that each of these conflicts is, at heart, an energy war.