from returning or gaining a foothold in raqqah again, they have to rebuild the fabric of society. >> arwa damian inside raqqah, remarkable work inside that city at great risk we might add as well, thanks to arwa. a threat from north korea this morning. the country says the united states should expect an unimaginable strike at an unimaginable time. >> this statement comes as the united states and south korea are carrying out more of these joint military drills over the peninsula. the language that john just gave you is similar to what we've heard from them previous state run media reports threatening to attack the united states and destroy the u.s. elise labott joins us with the latest. they use language like this all the time. anything significant that stands out to you this time? >> not really, poppy. i mean, look, as you said this is typical fare from south korea. they always get very excited, very angry when those exercises between the u.s. and south korea take place on the korean