This is waaaaaaaaaay too little news to get excited about. Where in Alaska? Innocuous explanations are perfectly possible. Was it found on the shoreline of one of the Aleutian islands? That would make perfect sense, since North Korea test fires missiles into the sea and the currents run that way.
Of course, if it was a fired missile that came down a few miles from Anchorage, I would be very concerned. ;)
The former Japanse PM was stating that Washington 'is underestimating the range of NK Missiles'
If that is the case would it be that suprising for a spent tested warhead to wash up on the Aleutian Island chain?