The hydrogen bomb, as North Korea claimed to have successfully tested, has an infinitely superior to nuclear power as used in Hiroshima and Nagasaki in 1945.
AFP
The atomic bomb releases energy by fission of elements such as uranium or plutonium.
The hydrogen or thermonuclear: using fission and fusion in a chain reaction.
At the moment it has not used any hydrogen bomb outside the sighting shots. Today, the US strategic nuclear arsenal, and certainly Russian, is composed exclusively of such devices, but in miniature with a very variable power.