BAGHDAD, Iraq - Angry Shiites marched Wednesday and set fire to the offices of a secular politician after a Sunni Arab guest criticized Iraq's Shiite religious leaders during an Al-Jazeera talk show. Al-Rubaei made his comments during the "Opposite Direction" program shown Tuesday night and Wednesday afternoon on Al-Jazeera. Hours later, thousands of people chanted anti-Al-Jazeera slogans in the streets of the Baghdad neighborhoods of Sadr City and Karradah, and in the southern cities of Najaf and Karbala. The demonstrations, which turned into political rallies, threatened to further polarize Thursday's parliamentary elections after angry Shiites in the southern city of...