The ballistic approach is better than having a nuke in orbit, since you can design a specific ballistic trajectory for any target. If you have a nuke in orbit, it would take a lot of energy to have the nuke re-enter and it would need to have precision maneuvering ability to vector itself to the target. The orbit will constrain you to targets near your ground track and you may not fly over your target for many days.
I was assuming that N. Koreans wouldn't mind lack of precision as long as they can send it to some general area with large population. Their weapon program is always geared to deliver maximum psychological effect. There is no way they can win a war with this nuke.
What I meant was that the minimum energy required to deliver a payload to any point on the earth via a ballistic trajectory is always less than the minimum energy needed to place the same payload in orbit. Since North Korea and Europe are both pretty high in the Northern Hemisphere, the minimum energy to hit a point anywhere in Europe is considerably less than orbital energy. Get a globe and a string and measure the great circle route to points in Europe. (It will pass near the north pole.) Even Greece is closer to Korea than the east coast of the United States, and a lot less than 180 degrees of arc away.