Petro-aggression occurs when a revolutionary government comes to power in a petrostate (an oil-exporting country). Oil on its own does not cause international aggression. But the combination of oil and revolution is dangerous. One study suggests that petro-revolutionary states are 250 percent more likely to instigate international conflicts than a typical country.
It remains unclear whether the pattern of petro-aggression found in oil-rich countries also applies to other natural resources besides oil.