FREEDOM AND SAFETY
North Korea has said it has carried out a “higher level” nuclear warhead test explosion which will allow it to finally build “at will” an array of stronger, smaller and lighter nuclear weapons.
It is Pyongyang’s fifth atomic test and the second in eight months.
South Korea’s president, Park Geun-hye, called the detonation, which Seoul estimated as the North’s biggest-ever explosive yield, an act of “fanatic recklessness”.
The North’s boast of a technologically game-changing nuclear test defies both tough international sanctions and long-standing diplomatic pressure to curb its nuclear ambitions.
Hours after Seoul noted unusual seismic activity near the North’s north-eastern nuclear test site, Pyongyang said in its state-run media that a test had “finally examined and confirmed the structure and specific features of movement of [a] nuclear warhead that has been standardised to be able to be mounted on strategic ballistic rockets”.
“The standardisation of the nuclear warhead will enable [North Korea] to produce at will and as many as it wants a variety of smaller, lighter and diversified nuclear warheads of higher strike power,” the North said.
“This has definitely put on a higher level [the North’s] technology of mounting nuclear warheads on ballistic rockets.”
North Korea protects its nuclear programme as a closely guarded state secret, and the claims about advancements made in its testing could not be independently verified.
But they centre on a technological mystery that has long bedeviled outside experts: How far has North Korea got in efforts to consistently shrink down nuclear warheads so they can fit on long-range missiles?
South Korea’s main spy agency told politicians in a closed-door briefing after the test that it does not think Pyongyang currently has the ability to develop miniaturised nuclear weapons which can be mounted on ballistic missiles, but intelligence officials expressed worries that the North’s efforts to do so are progressing quicker than previously thought, said Kim Byungkee, of the opposition Minjoo Party.
South Korea’s weather agency said the explosive yield of the North Korean blast would have been 10 to 12 kilotons, or 70-80 per cent of the force of the 15-kiloton atomic bomb the US dropped on the Japanese city of Hiroshima in 1945. The North’s fourth test was an estimated six kilotons.
A 5.0 magnitude earthquake on Friday is the largest of the four past quakes associated with North Korean nuclear tests, according to South Korea’s weather agency.
North Korean leader Kim Jong Un has overseen a robust increase in the number and kinds of missiles tested this year. Not only has the range of the weapons successfully tested jumped significantly, but the country is working to perfect new platforms for launching them – submarines and mobile launchers – giving the North greater ability to threaten the tens of thousands of US troops stationed throughout Asia.
The country is thought to have a handful of rudimentary nuclear bombs and has spent decades trying to perfect a multi-stage, long-range missile to eventually carry smaller versions of those bombs. But its miniaturisation abilities are a mystery.
After several failures, North Korea put its first satellite into space with a long-range rocket launched in December 2012, and has since launched another satellite on a similar rocket. Experts say that ballistic missiles and rockets in satellite launches share similar bodies, engines and other technology.
In January, North Korea claimed to have conducted a hydrogen bomb test, but many foreign governments and experts were sceptical about the claim. After that test, some analysts said the country was likely to need only a couple more test explosions before acquiring a miniaturised warhead that could be mounted on a long-range missile.