of the Niger Delta, a militant group seeking to redirect oil revenues to the country’s impoverished southern states. In 2009, when President Umaru Musa Yar’Adua offered the militants an amnesty and monthly cash payments, the insurgency died down. His successor, Goodluck Jonathan, a southerner, promised to respect the amnesty and channel more funds to the region.

For a while, high oil prices enabled Jonathanto make good on some of his promises, even as entrenched elites in Abuja continued to pocket a substantial percentage of the country’s petroleum income. When prices began to plummet, however, he was confronted with mounting challenges. Pervasive corruption turned people against the government, feeding recruits into Boko Haram, the terror movement then growing in the country’s northern reaches; money intended for soldiers in the Nigerianof low oil prices.

Saudi leaders have recently come to recognize that this plan is no longer sustainable. In 2016, the Saudi budget has, for the first time in recent memory, moved into deficit territory and the monarchy has had to cut back on both its usual subsidies to and social programs for its people. Unlike the Venezuelans or the Nigerians, the Saudi royals socked away enough money in the country’s sovereign wealth fund to cover deficit spending for at least a couple of years. It is now, however, burning through those funds at a prodigious rate, in part to finance a brutal and futile war in Yemen. At some point, it will have to sharply curtail government spending. Given the youthfulness of the Saudi population -- 70% of