KUT, Iraq, (Reuters) - U.S. troops detained the eldest son of Iraq's powerful Shi'ite politician Abdul Aziz Hakim at a border checkpoint with Iran on Friday, Iraqi security force officials told Reuters. The U.S. military said it was checking the report. Ammar Hakim's convoy was stopped at the Badrah checkpoint in Wasit province as he returned from Iran, they said. It was not immediately clear why he had been detained. The Iraqi security sources said U.S. forces had taken him to forward operating base Delta, a U.S. camp in nearby Kut, capital of Wasit province. Ammar's father is leader of...