U.S. took time on Syrian investigation to reach high degree of confidence

The U.S. took several months to conduct its investigation of Syrian chemical weapon use to reach a high degree of confidence that the red line was crossed, the White House said on Friday.

Ben Rhodes, the White House's deputy national security advisor for strategic communications, made the statement on Friday during a daily press briefing. Rhodes responded to questions about the several months the U.S. spent to conclude that Bashar al-Assad's Syrian regime used chemical weapons against the opposition. Rhodes said the U.S. was driven by its intelligence assessments of potential incidents.

"In terms of the time from April, essentially what we had in April was an initial intelligence assessment, and the President's direction was to continue to investigate additional corroborating facts and information so that we could raise our confidence level," Rhodes said. "Because that was not a high-confidence assessment and we didn't feel like we had enough corroborated information to reach that high degree of confidence that this red line had been crossed."

Rhodes said the U.S. intelligence community was able to increase its confidence level by piecing together a picture of information over the last few weeks.

"What's been done in the course of the last several weeks is we've been able to piece together a broader information picture -- so you're able to take, for instance, an assessed incident of chemical weapons use, you're able to receive reporting from individuals who were there on the ground," Rhodes said. "We were able to review physiological samples that have been collected at the site. We were able to review open source reporting from social media and other things that speak to the use of chemical weapons in an area. And we were able to review our own intelligence reporting, which obviously covers a range of different means."

Rhodes declined to go into detail about what kind of lethal assistance the U.S. might provide to the Syrian opposition and the exact amount of time it would take the assistance to arrive.