Before we give Obama or Kerry too hard a time about this it is worth reflecting that the fully justified scepticism of Congress stems directly from Iraq and its dodgy dossiers and known unknowns.
Anyone who still feels it is a simple case of goodies versus baddies really ought to read the account of Domenico Quirico, Italian journo just released from the clutches of various factions of the Free Syrian Army. They are utterly vile! Most worryingly for us, the only time he was treated with a scrap of humanity was when in the hands of Al Qaeda!