How dangerous is North Korea’s nuclear programme?

The country, presided over by its young leader Kim Jong-Un, reported that Tuesday’s explosion, larger than its previous two tests, had been created by a miniaturised nuclear device.

The significance of this is that it accords with the view that North Korea is heading towards owning a long-range ballistic missile. A miniaturised device could, it is argued, be placed inside the 1.25-metere nose cone of North Korea’s Nodong missiles.

..a successful North Korean test of such of a compact design would bring it one step closer to being able to build a long-range ballistic missile. Shannon K Nile, SIPRI

Shannon K Nile, head of the nuclear weapons programme at the Stockholm International Peace Research Institute, said: “While it will be technically challenging for outside experts to confirm the design of the device, a successful North Korean test of such of a compact design would bring it one step closer to being able to build a long-range ballistic missile capable of delivering a nuclear weapon.

“In December 2012, North Korea successfully tested a multi-stage satellite launcher, suggesting that it was gradually mastering the technology needed to develop such a missile.”

Weapons-grade uranium

Attention has also focused on whether or not the device exploded used highly enriched uranium, or plutonium. It is believed that North Korea used plutonium in its previous two tests – and has only a limited supply of the element.

However, if North Korea is manufacturing weapons-grade uranium, then it would be easier to significantly expand its nuclear arsenal.

Mr Kile said: “By using highly enriched uranium for nuclear weapons, North Korea could potentially overcome the constraints posed by its limited stock of weapon-grade plutonium.

“North Korea currently has enough separated plutonium to construct six to eight nuclear explosive devices. A test using HEU could pave the way for an expanded future arsenal.”

Highly enriched uranium can be more readily fashioned into crude nuclear weapons by terrorists and other non-state groups. Mark Fitzpatrick, ISIS

He added that, as it appears the underground detonation was fairly shallow, airborne sampling techniques outside the country should be able to indicate what fissile material was used, and thus giving a greater insight into North Korea’s weapons capability.

Nuclear numbers

A study by the Institute for Science and International Security last summer predicted that, in the most weapons grade uranium productive environment, North Korea could have 48 nuclear weapons by the end of 2016.

This compares with around 240 warheads in China, 300 operational warheads in France and 225 warheads in the UK. Russia and the US are estimated to have more than 5,000 nuclear warheads each.

Not much is known about how significant North Korea’s nuclear armament programme is and much depends on whether or not a secret uranium enrichment plant exists in the country. One uranium enrichment facility exists at Yongbyon, but North Korea maintains this is used for producing low-grade uranium for generating power in a light-water reactor being constructed nearby.

There is still time to halt and reverse current trends before North Korea’s nuclear capabilities become more substantial. Daryl Kimball, Arms Control Association

This reactor, the report says, could be engineered to produce weapons-grade uranium. At the lower end of the spectrum, the report suggests North Korea’s nuclear weapons arsenal by the end of 2016 could number as few as 12 weapons.

Show of force

Mark Fitzpatrick, director of the non-proliferation and disarmament programme at ISIS, said: “North Korea has been working on warhead designs for about 25 years, and some experts believe it likely that by now it has a workable device.

“But North Korean generals would have wanted to be sure, and the political leadership would want the world to believe their country has such a weapon.

“After all, the purpose of the weapons is the defence of the regime, and deterrence depends on adversaries believing North Korea has both the will and the capability to employ nuclear force.”

He also warned that North Korea could sell weapons-grade uranium. “Highly enriched uranium can be more readily fashioned into crude nuclear weapons by terrorists and other non-state groups,” he said.

‘Still time’

The threat of North Korea developing an intercontinental ballistic missile (ICBM) that would reach its number one enemy the United States is “years away”, says Daryl Kimball from the Arms Control Association, a US-based research and advocacy group.

“It is likely to be years away from fielding an ICBM, which could deliver a nuclear warhead to the US mainland,” he said. “There is still time to halt and reverse current trends before North Korea’s nuclear capabilities become more substantial.”