U.S.-backed Syrian fighters have surrounded the Islamic State-held city of Manbij from three sides as they press a major new offensive against the jihadists near the Turkish border, a spokesman for the fighters said on Monday. But in a sign of the difficulty world powers have faced in building a coalition to take on the self-declared caliphate, the slow pace of a separate assault by the Iraqi army on a militant bastion near Baghdad caused a rift between the Shi’ite-led government and powerful Iranian-backed Shi’ite militia. The simultaneous assaults on Manbij in Syria and Falluja in Iraq, at opposite ends of Islamic State territory, are two of the biggest operations yet against Islamic State in what Washington says is the year it hopes to […]