North Korea has restarted it's research reactor and is thought capable of producing sufficient plutonium, from 8,000 spent fuel rods, for five or six nuclear bombs over the next few months. The US asserts that North Korea already has one or two bombs, although North Korea has apparently not tested their nuclear bomb design yet. 

American credit rating agencies warned South Korea and Japan that their credit ratings would decline if North Korea openly admitted to having nuclear weapons. This would mean slower economic growth because of higher borrowing costs and more difficulty raising investment capital.