The road mentioned above does not pass through economic hubs. Trans-Korean railway can go either along E. Coast(to Russia) or W. Coast(to China) of Korea.
Russia and China both see running the Railway through N.Korea and/or access to would be the solution for N.Korea...Not that I agree with them, but that is how ‘they see’ the solution..as an economic one by lifting N.Korea into the World Trade Markets. Thus giving them recognition as a world trade partner etc.