Is So. Korea really skeptical?... South Korea skeptical of North's hydrogen bomb claims Jan. 6, 2016 -- The probability North Korea conducted a hydrogen bomb test is low, South Korea military and intelligence officials said Wednesday, after Pyongyang announced it had successfully tested a hydrogen bomb. See also: South Korea seeks U.S. strategic weapons after North's nuclear test Thu Jan 7, 2016 - South Korea is in talks with the United States to deploy U.S. strategic weapons on the Korean peninsula, a South Korean military official said on Thursday, a day after North Korea said it successfully tested a hydrogen nuclear device.
Well, I'm skeptical. It is highly implausible that a program as rudimentary as North Korea's would be able to produce thermonuclear weapons. I can believe that they have boosted A-bombs though.