To help focus minds before a recent call, I was asked to prepare a slide called ‘Medium-Term Economic Risks/Challenges for Ireland’.  As a strong advocate of the JK Galbraith maxim: ‘There are two types of forecasters: those who don’t know, and those who don’t know they don’t know’, I was reluctant to comply. But on reflection, the framework infamously outlined by the then US Defence Secretary, Donald Rumsfeld, in 2002 offered help: ‘There are known knowns. There are things we know we know. We also know there are known unknowns. That is to say, we know there are some things…