Mark Nelson is the managing director of the Radiant Energy Fund, which advises non-profits and industry about nuclear energy. Nelson, who spent much of the last two months in Europe, explains why the continent’s energy crisis is the result of decades of complaisance about energy infrastructure, why Britain is in worse shape than other European countries, how deregulation of the UK’s electric market fueled the disaster, why Germany has to preserve its nuclear fleet, and why Europe could be facing energy shortages for years to come.