Lingering doubts over Syria gas attack evidence

The US government insists it has the intelligence to prove it, but the American public has yet to see a single piece of concrete evidence no satellite imagery, no transcripts of Syrian military communications connecting the government of President Bashar Assad to the alleged chemical weapons attack last month that killed hundreds of people.
In the absence of such evidence, Damascus and its ally Russia have aggressively pushed another scenario: that rebels carried out the August 21 chemical attack. Neither has produced evidence for that case, either. That's left more questions than answers as the US threatens a possible military strike.

The early morning assault in a rebel-held Damascus suburb known as Ghouta was said to be the deadliest chemical weapons attack in Syria's two and a half year civil war. Survivors' accounts, photographs of many of the dead wrapped peacefully in white sheets and dozens of videos showing victims in spasms and gasping for breath shocked the world and moved President Barack Obama to call for action because the use of chemical weapons crossed the red line he had drawn a year earlier.
Yet one week after Secretary of State John Kerry outlined the case against Assad, Americans at least those without access to classified reports haven't seen a shred of his proof.

There is open-source evidence that provides clues about the attack, including videos of the rockets that analysts believe were likely used. Some experts also think the size of the strike, and the amount of toxic chemicals that appear to have been delivered, make it doubtful that the rebels could have carried it out.
The Obama administration, searching for support from a divided Congress and skeptical world leaders, says its own assessment is based mainly on satellite and signal intelligence, including indications in the three days prior to the attack that the regime was preparing to use poisonous gas.
But multiple requests to view that satellite imagery have been denied, though the administration produced copious amounts of satellite imagery earlier in the war to show the results of the Syrian regime's military onslaught.

When asked Friday whether such imagery would be made available showing the August 21 incident, a spokesman referred The Associated Press to a map produced by the White House last week that shows what officials say are the unconfirmed areas that were attacked.