http://www.telegraph.co.uk/news/2017/04/06/left-of-launch-attacks-may-bringing-north-korean-missiles/
Quick read - all speculation, maybe the USA has something to do with the recent Korean Launch failures.
Just thinking, what a perfect opportunity to "test" emerging technologies, at minimal expense!
Like a bunch of guys all hanging around with Shot Guns and a Clay Pigeon thrower, arguing over who gets to take -out- the next missile... Translated to weapons experts, "OK, we know they're gonna launch one... who goes first?
Laser weapons guy raises his hand, "Me, Me, Me!"
Hyper-sonic guy, "you got the LAST one, before my 'dart' got there - I go first next time!"
Rail Gun guy, "Yea! You guys gotta let it get to the horizon, so I can get a chance at it - quit cheating!!"
Software/Maleware guy... trying to pretend he isn't in the room, until someone notices him, "HEY!!! Don't start that crap, I waited and waited - this one is on the Fat Guy, my infection doesn't kick in for another 30 seconds...!"
Stuxnet 2, anyone?