Countries are arguing over how to cope with the scale of the worst humanitarian crisis since World War II. German Chancellor Angela Merkel said all European Union countries have a duty to offer shelter to refugees arriving on their soil, rebuffing Hungarian Prime Minister Viktor Orban who called the region’s biggest flood of refugees since World War II a “German” problem. Meanwhile, British Prime Minister David Cameron is preparing to bow to pressure both from within Britain and from European allies and let in thousands more refugees, according to a person familiar with his plans.