The use of chemical weapons by the Assad regime was supposed to be a red line.

Two days ago, when Israel suggested chemical weapons had been used, it was dismissed as Israel trying to maneuver U.S. policy.

The U.S. now has evidence that such weapons were used, and that the Assad regime was the source.

But the evidence is not conclusive, just very strong.

White House: US believes Syrian regime used chemical weapons:

The White House said Thursday that the U.S. believes “with some degree of varying confidence” the Syrian government has used chemical weapons — specifically the nerve agent sarin — against its own people.

A letter from the White House to members of Congress said the assessment was based on “physiological samples” but more information is needed to corroborate it and nail down when and how they were used.

Secretary of State John Kerry told reporters at the Capitol that the U.S. believes chemical weapons were used twice, but the letter doesn’t specify that.

“Our intelligence community does assess with varying degrees of confidence that the Syrian regime has used chemical weapons on a small scale in Syria, specifically the chemical agent sarin,” the letter said.

“We do believe that any use of chemical weapons in Syria would very likely have originated with the Assad regime,” it added.

Chuck Hagel made a similar statement to reporters.

“Does this cross the red line?”  Hagel was equivocal, and deferred policy to Obama:

Syrian Blood Tests Positive for Sarin Gas, U.S. Spies Say:

The U.S. intelligence community has uncovered strong evidence that chemical weapons have been used in Syria. Several blood samples, taken from multiple people, have tested positive for the nerve agent sarin, an American intelligence source tells Danger Room. President Obama has long said that the use of such a weapon by the Assad regime would cross a “red line.” So now the question becomes: What will the White House do in response?

Given how Obama has attacked Bush over Iraq WMD’s, the hurdle will be pretty high for the administration to declere the red line crossed.

Does remind me of Branco’s cartoon:

Lines in the sand