Nigeria, June 12 -- In 1956, the year Egypt's Gamal Abdel Nasser shook the global order by nationalising the Suez Canal, and Morocco, Tunisia, and Sudan tasted the exhilarating air of independence, something equally historic happened beneath Nigerian soil. At Oloibiri, decades of prospecting ended in a dramatic geyser of crude oil and with it, the promise of a nation "flowing with milk and honey".

That promise was not entirely hollow.

Oil revenues built roads, funded institutions, and kept a fragile post-civil-war economy breathing. For a young nation assembling itself from the ground up, petroleum was a genuine lifeline.

But 40 billion barrels later, oil's contribution to Nigeria's prosperity has fallen dramatically short of what was ...