Syria: Reports of chemical weapons use challenge Obama’s ‘red line’

A day after Israel's head of research for military intelligence declared, "Our assessment is that the [Assad] regime has used and is using chemical weapons," the response from Washington remains muted.

US Secretary of State John Kerry and White House spokesman Jay Carney both said there was not yet concrete evidence of the use of chemical weapons in Syria.

"We have not come to the conclusion that there has been that use," Carney told reporters. "It is precisely because of the seriousness of the use of chemical weapons — and the seriousness with which the president made clear that that use would be unacceptable — that it is incumbent upon us and our partners to investigate thoroughly and validate or verify allegations of chemical weapons use."

Israeli Brig. Gen. Itai Brun made the statement about chemical weapons on Tuesday at a national security conference in Tel Aviv, a week after news that the French and British governments had sent the United Nations letters with similar allegations in March.

A senior US defense official quoted by Reuters said, "The letter did not provide conclusive evidence of chemical weapons use, but did request a UN investigation into all allegations of use in Syria."

The statements of doubt from US officials come in the line of President Barack Obama defining the use of chemical weapons in Syria as a "game-changer" or "red line."

Syria is believed to have both mustard gas and the nerve agent sarin, and the government and rebels have each blamed the other for use of chemical weapons.

Already, the United States' reluctance to act on the reports is eliciting scorn from voices in the Syrian opposition. Hisham Marwa, a senior member of the National Opposition Coalition said, "The US said that the use of chemical weapons was a red line for the Assad regime but the regime is using them and nothing has happened," according to the Guardian.

GlobalPost Senior Correspondent in Jerusalem, Noga Tarnopolsky, said there seemed to be a number of takeaways from the recent news about chemical weapons in Syria.

"The first thing to keep in mind is that no one has questioned the substance of Gen. Itai Brun's statements about the use of sarin gas in Syria," Tarnopolsky said. "We therefore have to assume the uncomfortable limbo that has ensued does not touch upon his assertion. I think it is safe to assume Europe, the United States and Israel are in agreement on this subject."

"Brun is a very highly regarded figure in the intelligence community, so it is not entirely surprising that his information is holding up. The general assumption in Israel is that he would not have spoken unless he was in possession of incontrovertible physical evidence."

Tarnopolsky said that it is possible the general just spoke out of turn. "This goes without saying, but he is a military man, not a diplomat."