BAGHDAD – Iraq's prime minister has told Mahdi Army militiamen they must surrender their arms or face an all-out assault by U.S.-backed Iraqi forces, senior Iraqi officials said Wednesday, revealing a pledge Washington wanted to hear as American and Iraqi troops prepared a fresh operation to end the bloody sectarian war gripping Baghdad. The blunt message was particularly significant given that Nouri al-Maliki, the Iraqi leader, previously had blocked several U.S. attempts to crack down on the military wing of radical anti-American Shiite cleric Muqtada al-Sadr, now one of the most powerful players in Iraq. "Prime Minister al-Maliki has told...
