A still more basic issue is finance. Rebuilding the north may start with small pilot projects, but if successful the costs can only escalate. But this may be wishful thinking, or it may rebound. Talk of North Korea joining the likes of the World Bank ignores how much it would have to disclose and reform to be eligible. That leaves private capital.
Foreign companies are unlikely to rush to Pyongyang, except in partnership with Korean firms.
So the political price of north-south amity will be a slacking in southern reform. Realistically too, South Korea's already stretched public finances will be further put upon, or the tab will be passed to the taxpayer. Bonds are another likely option. But thorny issues will arise as to how far southern aid means opening, or opening entails reform. Both efficaciousness and reciprocity are involved.