After a year in which global business was buffeted by macroeconomic concerns and geopolitical factors, the outlook for 2020 is likely to be dominated by the very same considerations. However, with a presidential election looming in the US and a host of “black swans” (such as the killing on Friday of Qassem Soleimani, Iran’s top general) on the international horizon, the potential for further economic volatility is, arguably, greater than ...