North Korea proclaimed itself a ` ` nuclear state '' in a revised constitution this year . Russia : Appears to be angry at the U.S. as the rhetoric from Russia rises . North Korea previously announced its nuclear capability through its state-run broadcaster and newspapers , `` but no expression can be stronger than including it in their constitution , '' Professor Choi Jong Kun of Yonsei University told CNN . ` Comes as signs are growing of unrest at North Korea 's nuclear test site .
North Korea proclaimed itself a ` ` nuclear state '' in a revised constitution this year . Russia : Appears to be angry at the U.S. as the rhetoric from Russia rises . Comes as signs are growing of unrest at North Korea 's nuclear test site .