This can be a real threat. There is no doubt that North Korea can make a bio weapon, but the problem is that just one small leak could kill thousands in North Korea, if not millions. Bio weapons are hard to control, which is why most countries do not do much with them. Iraq was reported to have started a program, but had leaks almost immediately,causing them to concentrate on chemical weapons that were much easier to control. North Korea has a robust chemical weapons program as well, no where near the size of the former Iraq program, but still sizable. North Korea has a pest problem that requires them to use pesticides to stem the problem. Pesticide plants can be turned to chemical weapons plants, within hours in some cases. Many pesticides are basically low grade chemical weapons. Mexico has had problems with chemical plant malfunctions that made pesticides and have killed thousands over the last 10 years or so. ISIS has talked about using chemical weapons in their magazines and web sites.