North Korea said it has “succeeded in making a more developed” hydrogen bomb and mounting it on the tip of a long-range missile, and threatened a high-altitude nuclear blast that experts fear could wipe out electrical networks in the U.S. Leader Kim Jong Un witnessed a hydrogen bomb being mounted onto a new intercontinental ballistic missile while visiting the Nuclear Weapons Institute, North Korea’s state media reported Sunday. Kim in the report boasted that all of the components of its thermonuclear weapon are homemade, insulating the nuclear-weapons program from sanctions and “enabling the country to produce ... (full story)