Double dip. It is the phrase on everyone's lips – and it makes many of those lips tremble. With the shock of 2008 fading into memory, the moment of reckoning for the global economy has arrived. Will the bounce back from the nadir become established as a return to sustainable expansion – or will initial relief mutate into the despair of a renewed slowdown?

There is no doubt that the mood has soured since spring as Europe's authorities flapped in the face of a sovereign debt crisis, thus intensifying its effects. Just take a – however unscientific – survey of English- language media over the past six months: while mentions of a V-shaped recovery have remained constant, references to a double dip have soared. They were almost four times as high in July as in May.

Such talk is fuelling the doom- mongers. Chief among them, Nouriel Roubini, chairman of Roubini Global Economics, argued last week that a downturn in the global economy “will accelerate in the second half of the year”. For Europe and Japan, “avoiding double-dip recession will be difficult”, he said. Indeed, right on cue, manufacturing activity indicators weakened in June for China, South Korea, Taiwan, India and Australia.