The Obama administration says it is certain Assad forces carried out the chemical attack on August 21st that killed nearly 1,500 people in Syria. What's not certain is how America will respond. President Obama is trying to convince his country AND the international community that military action is needed, but, he now says there may be merit in the Russian proposal that Assad put his chemical weapons under intentional supervision.

HARDtalk speaks to PJ Crowley, former US assistant secretary of state for public affairs. How far has Obama's Syria policy been defined by ambiguity and change, and has this eroded Obama's credibility and authority? Show less