Washington considers the latest nuclear test by North Korea a threat to America?s national security and has threatened ?swift and credible action? against Pyongyang. Earlier, the US said preemptive military strike against DPRK is an option.
The US ?will also continue to take steps necessary to defend ourselves and our allies,? President Barack Obama said in a statement, adding that Washington will be ?vigilant in the face of North Korean provocations and steadfast in our defense commitments to allies in the region.?
http://rt.com/usa/news/nuclear-korea-threat-usa-003/