Photos released by North Korea showed Kim talking with his lieutenants as he observed a silver, peanut-shaped device that was apparently the purported thermonuclear weapon destined for an ICBM.
Aside from the factuality of the North's claim, the language in its statement seems a strong signal that Pyongyang will soon conduct another nuclear weapon test, which is crucial if North Korean scientists are to fulfill the national goal of an arsenal of viable nuclear ICBMs that can reach the U.S. mainland. There's speculation that such a test could come on or around the Sept. 9 anniversary of North Korea's national founding, something it did last year.
As part of the North's weapons work, Kim was said by his propaganda mavens to have made a visit to the Nuclear Weapons Institute and inspected a "homemade" H-bomb with "super explosive power" that "is adjustable from tens kiloton to hundreds (of) kiloton," the state run Korean Central News Agency said.
North Korea in July conducted its first ever ICBM tests, part of a stunning jump in progress for the country's nuclear and missile program since Kim rose to power following his father's death in late 2011. The North followed its two tests of ICBMs, which, when perfected, could target large parts of the United States, by threatening to launch a salvo of its Hwasong-12 intermediate range missiles toward the U.S. Pacific island territory of Guam in August.
It flew a Hwasong-12 over northern Japan last week, the first such overflight by a missile capable of carrying nukes, in a launch Kim described as a "meaningful prelude" to containing Guam, the home of major U.S. military facilities, and more ballistic missile tests targeting the Pacific.
To back up its bombast, North Korea needs to conduct nuclear tests. The first of its two such tests last year involved what it claimed was a hydrogen bomb; the second it said was its most powerful detonation ever. Experts and outside governments are skeptical of the hydrogen claim, but it is almost impossible to independently confirm North Korean statements about its highly secret weapons program.
It is clear, however, that each new missile and nuclear test gives the North invaluable information that allows big jumps in capability. A key question is how far North Korea has gotten in efforts to consistently shrink down nuclear warheads so they can fit on long-range missiles.
"Though we cannot verify the claim, (North Korea) wants us to believe that it can launch a thermonuclear strike now, if it is attacked. Importantly, (North Korea) will also want to test this warhead, probably at a larger yield, to demonstrate this capability," said Adam Mount, a senior fellow at the Center for American Progress.
North Korea's claim that "this warhead is variable-yield and capable of specialized weapons effects implies a complex nuclear strategy. It shows (North Korea) is not only threatening assured destruction of the U.S. and allied cities in the event it is attacked, but also that (North Korea) is considering limited coercive nuclear strikes, or is seeking credible response options for U.S. ones."
North Korea is thought to have a growing arsenal of nuclear bombs and has spent decades trying to perfect a multistage, long-range missile to eventually carry smaller versions of those bombs.
South Korea's main spy agency has previously asserted that it does not think Pyongyang currently has the ability to develop miniaturized nuclear weapons that can be mounted on long-range ballistic missiles. Some experts, however, think the North may have mastered this technology.
In Washington, there was no immediate reaction from the White House or the State Department.
The North said in its statement Sunday that its H-bomb "is a multi-functional thermonuclear nuke with great destructive power which can be detonated even at high altitudes for super-powerful EMP (electromagnetic pulse) attack according to strategic goals."
Kim, according to the statement, claimed that "all components of the H-bomb were homemade ... thus enabling the country to produce powerful nuclear weapons as many as it wants."
In what could be read as a veiled warning of more nuclear tests, Kim underlined the need for scientists to "dynamically conduct the campaign for successfully concluding the final-stage research and development for perfecting the state nuclear force" and "set forth tasks to be fulfilled in the research into nukes."
Associated Press writers Youkyung Lee and Kim Tong-hyung contributed to this report.
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