Citing sarin use, U.S. seeks Congress' OK for action

Sunday, September 1, 2013 | 6:46 p.m. CDT

WASHINGTON — The Obama administration geared up for the biggest foreign policy vote since the Iraq war by arguing Sunday that new physical evidence shows the Syrian government used sarin gas in a deadly August attack. With its credibility on the line, the United States must respond, the country's top diplomat said.