Germany must be ready to pay a hefty price for Chancellor Angela Merkel’s decision to lay out a welcome mat for any and all Middle East migrants who make it across the country’s borders. A German economist has warned that cost will come in massive tax hikes levied sooner rather than later. The reason German workers will be left with the tab is that most new arrivals are low skilled and will be dependent on social benefits including public housing, food and clothing for years after their arrival. At the same time they are taking from a system they contribute...