"If the Syrian government had nothing to hide

"If the Syrian government had nothing to hide and wanted to prove to the world that it had not used chemical weapons in this incident, it would have ceased its attacks on the area and granted immediate access to the U.N. five days ago," a senior White House official said.
"At this juncture, the belated decision by the regime to grant access to the U.N. team is too late to be credible, including because the evidence available has been significantly corrupted as a result of the regime's persistent shelling and other intentional actions over the last five days," the official added.
The official said that—based on the reported number of victims, the reported symptoms of those who were killed or injured and other information—"there is very little doubt at this point that a chemical weapon was used by the Syrian regime against civilians in this incident."

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U.S. Talks Tough on Syria, Ramps Up Attack Planning

More evidence is being gathered by all nations now regarding War Crimes against Assad and his government to be tried in International Court in Europe at some point similar to Milosovic.