North Korea claims it successfully conducted hydrogen bomb test. (NBC News)
H-bomb: more powerful than Hiroshima bomb, fits on missile. (AP)
SC Gov Nikki Haley to give the Republican response to the State of the Union address. (AP)
Rep. Steve Israel, a top House Democrat, won't seek reelection. (New York Times)
Sheriff says steps being taken to end militants' occupation of federal compound. (The Oregonian)
FBI: 18 minutes missing in San Bernardino shooting timeline. (USA Today)
Saudi-Iran feud poses threat to Iraq's effort to combat ISIS. (New York Times)
What are you reading this morning? Let us know in the comments, please.