Tanzania’s government sent in the army last week, not to repel an invading force nor crush a terrorist threat. The army’s instructions were clear: buy cashew nuts.

The intervention, which sent global cashew prices higher, was intended to resolve a dispute between buyers of the unprocessed nut and farmers. John Magafuli, Tanzania’s president and an African Hugo Chávez in the making, was reacting to a fall in prices. Because of a bumper west African harvest, raw cashew prices had fallen across the world. Tanzania, the seventh-largest producer, is a swing supplier of the chattering classes’ favourite cocktail snack. After requisitioning the east African country’s entire supply, prices rose.

This is not the first time Mr Magafuli has intervened in global commodity markets. Last year, he accused Acacia Mining — majority owned by Barrick Gold — of massively understating the mineral levels in its gold and copper exports. Acacia had operated in the country for years, made good profits and paid its executives handsomely, Mr Magafuli noted. But it had somehow avoided paying much tax in Tanzania.