Nuclear security

Why is North Korea’s ‘hydrogen bomb’ test such a big deal?

Regardless of whether the explosion was atomic or thermonuclear, it was a brazen provocation and a clear defiance of international treaties. So get ready for lots of international condemnation and some stern words at the United Nations. Already North Korea's neighbors — South Korea, Japan and China — have strongly criticized the test, and the United States is getting ready to do so, once it's confirmed. The U.N. Security Council is set to hold an emergency meeting.