hydrogen bomb

Analysts believe it was 17 times as strong as the bomb that fell on Hiroshima.
Leader Kim Jong Un inspected the bomb, which can be mounted to an intercontinental ballistic missile.
Any nuclear test would be a "flagrant violation" of U.N. Security Council resolutions, the White House said.
Fortunately, experts aren't convinced that North Korea really tested one.
Some experts doubt the latest saber-rattling claim.