south korean navy ship that killed 46 sailors. also headed the top secret unit thought to be sresponsible for the sony hack. >> it's a signal that while north korea is now willing to engage with the south, they are not going to alter their military plans or their icbm plans or any of their programs to threaten, not only the united states, but its allies. >> analysts say the days and weeks after the para olympics end in march will be crucial. u.s. and south korea have said they'll resume joint military exercises then, which could prompt kim jong-un to test more missiles. but it could also go the other way with possible summit in pyeongchang between moon and kim jong-un summit proposed but they have not committed to. >> i suppose they'll be meeting with officials as well? >> that's right.