Forget about their nuclear weapons capabilities. North Korea's new weapon of choice is water.
This is not a joke. Apparently, the breaching of a dam in the north that sent water surging into South Korea killing six in the south and at least one child in the north whose body was swept into South Korea was not an accident but an intentional attack.
North Korea has built a series of dams in the higher elevations overlooking South Korea and there's long been fear in the south that they would used to launch water attacks on the south.