NKorea vows to nuke US

today i read that north Korea has vowed to launch a pre emp nuclear strike.north Korea will exercise its right for a preemptive nuclear attack to destroy the strongholds of the aggressors because is pushing to start a nuclear war against the North.
  Although North Korea boasts of nuclear bombs and pre-emptive strikes, it is not thought to have mastered the ability to produce a warhead small enough to put on a missile capable of reaching the U.S. It is believed to have enough nuclear fuel, however, for several crude nuclear devices.he U.N. Security Council was considering a fourth round of sanctions against Pyongyang in a fresh attempt to rein in its nuclear and ballistic missile programs