Secretary of State John Kerry’s description of the planned US military response to the Ghouta massacre as likely to be “unbelievably small” almost derailed the utility of the US threat in concentrating Syrian and Russian officials’ minds. And the administration could have helped itself by better explaining that a cooperative response to the Assad regime’s use of chemical weapons had long been on the table, and was not just the result of deftly opportunistic Russian diplomacy in response to a Kerry thought-bubble.