BAGHDAD — As Iraq’s prime minister struggles to meet his goal of retaking Mosul from the Islamic State group by the end of this year, he also is racing to prevent a power struggle with radical Shiite cleric Muqtada al-Sadr.A victorious war leader, Prime Minister Haider al-Abadi is striving to unite the country’s quarreling factions and take the wind out of Sheikh al-Sadr’s protest movement that has brought tens of thousands onto the streets in defiance of government calls for a halt on demonstrations that distract from the fight against the Islamic State. But some doubt he will achieve it, saying Mr. al-Abadi will preside over an ever-weakening government.
