Even if everything Secretary of State John Kerry says about chemical weapons in Syria were true, the evidence would prove only that Bashar al-Assad committed crimes against civilians. It would not prove that the U.S. government has either the moral or legal authority to commit acts of war.
These issues must be kept separate. We have reason to be skeptical of Kerry’s case — why did President Obama try to stop the UN inspection? — but if it were otherwise, the case for U.S. military intervention still would not have been made — even if authorized by Congress.