Stephen Sackur speaks to Otmar Issing, influential German economist and former board member of the European Central Bank. The European economy just about survived the post-crash era of recession, debt crisis and emergency bailout, but its resilience is about to be tested again. Global growth is sluggish, Europe's banks still look fragile, and the EU is full of political uncertainty. Germany has long been Europe's rock of stability, but for how much longer? Should Europe brace itself for new economic storms?