March 5 will be marked in red in crude chronicles. That day, a carefully-seamed pact to cut global oil supply—between rivals Saudi Arabia and Russia, among other producers—was torn apart. Its demise kick-started a war between the US, Saudi Arabia and Russia that threatens to collapse prices to unprecedented levels. Such a scramble for market share has been seen before. However, this time two black swans twist the tale into unprecedented, and menacing, territory.