re: Who’s buying: An EMP attack by North Korea could shut down the US power grid and kill '90%

Total BS. The 90% number was pulled from a University of Colorado study about the worst-case effects on the power grid in the event of a Carrington level solar storm. EMP and CME are two totally different animals in terms of effects on electrical grids and their components. Read the Lloyds of London report on insurable loss due to solar activity if you really want an eye-opener.