North Korea is a mortal nuclear threat to the United States, right now! Any nuclear weapon detonated above an altitude of 30 kilometers (18 miles) will generate an electromagnetic pulse (EMP) that will destroy electronics and could collapse the electric power grid and other critical infrastructures — communications, transportation, banking and finance, food and water — that sustain modern civilization and the lives of 300 million Americans. All could be destroyed by a single nuclear weapon making an EMP attack. By Peter Pry. Read Full Story