Back in 2012, a star of the global commentariat declared that oil prices would “skyrocket to permanently higher levels”. Since then, the price of a barrel of Brent crude has plummeted by more than 40 per cent, proving yet again the folly of making predictions.With this cautionary tale in mind, let me offer some thoughts on how the two great crises of this year – Russia’s shadowy invasion of Ukraine and the advance of Islamic State across the Middle East – might develop in 2015.In both situations, I think there are grounds for cautious optimism, and for reasons that, oddly enough, relate to the arguments of the economist who got things so spectacularly wrong two years ago.Dambisa Moyo (for it was she) took time off the conference circuit in 2012 to write a ter