warning the russians and syrian government that chemical weapons cannot be used. so far, the warnings have not been heeded by the russians or syrians. they are gearing up for the offensive. you have the summit in the iranian capital with the turks and iranians as well. those sides will try to prevent major bloodshed from happening. very difficult to see how that will be done. russians saying this last place called idlib province is a terrorism province. there are jihadist group there is and affiliations with al qaeda. a situation heating up. a possible conflict with u.s. and russia is something that could be in the cards in the future. especially with the u.s. seemingly getting tougher on syria all together. dave. great reporting, fred. thank you. breaking overnight. defense secretary james mattis touching down in afghanistan.