NK smuggles a shipping container into SK. SK unwittingly puts the shipping container on a ship sailing to the US West Coast.As of now, North Korea lacks the necessary delivery system. And if they did, we have systems in place to shoot their missiles out of the sky (or low orbit).
The container is trucked to Los Angeles.
Fucking BOOM!
What part of this journey is difficult?
Don't bother replying the trip from NK to SK. Goods are smuggled by sea all the time between the country's.