Workers adjust a valve of an oil pipe in Tawke oil field near Dahuk, 400 km (248 miles) north of Baghdad, November 14, 2011. Iraq's oil sector was limping along after years of sanctions and conflict following the U.S. invasion in 2003, and badly needed more investment. But bringing in Big Oil could expose a vulnerable country to rapacious bids and exploitation. REUTERS/Azad Lashkari