The U.S. inches closer to striking targets in Syria, with warships in place and the administration saying there is "no doubt" that chemical weapons were used by the al-Assad regime. Wolf Blitzer will go in depth again with guests, analysts and reporters from around the world to examine the U.S.'s military options and debate the merits of a Western intervention. Tune in at 6p ET - only on CNN.

Sen. Jack Reed, a top Democrat from Rhode Island, urges the Obama administration against taking unilateral military action in Syria and explains why.