Greed for petroleum has produced plenty of war. War can be defined narrowly, as conflict between nations, or broadly, as large-scale violence in pursuit of gain. This is why so many see the climate movement as a peace movement – especially after the recent massacres in Paris.
In the fossil-fuel era, some oil corporations became powers equal to states, and some states became petroleum corporations in drag, and both were eager to fight horrific wars over resource control. The abuse of power and the destruction go all the way back to the early history of the petroleum industry in particular (though coal and natural gas extraction and industries have plenty of ugly achievements of their own).