In a remote and arid corner of southwestern Pakistan, Islamabad has found itself embroiled in a difficult battle: a multibillion-dollar dispute with a global mining company over one of the world's richest untapped deposits of copper and gold. In July, the World Bank's International Centre for Settlement of Investment Disputes (ICSID) ordered Pakistan to pay $5.9 billion in damages to the Tethyan Copper Co., a joint venture between Canada's Barrick Gold Corp. and Chile's Antofagasta PLC. The ruling stems from a 2012 case that Tethyan lodged at the ICSID against Islamabad for failing to issue a license to mine gold and copper at the Reko Diq site. The case draws attention to the rich resources of Balochistan, Pakistan's rugged southwestern frontier in which Reko Diq is located, as well as the tug of war between domestic Pakistani law and international arbitration in resolving investor disputes. But above all, the Reko Diq...