Analysts say North Korea's successful launch of a long-range rocket is a major achievement for a country that has long wanted to obtain the capability to strike North America with nuclear weapons. But they say Pyongyang must still make several major technological advances before that threat becomes a reality.
South Korea's Defense Ministry on Thursday acknowledged the launch succeeded in placing a satellite into space, even if it could not confirm whether it was functional. Spokesperson Kim Min-seok said the satellite weighs about 100 kilograms, far less than the payload of a nuclear warhead.
"A nuclear warhead weighs about 650 kilograms. [To have the full capability to launch an intercontinental ballistic missile, or ICBM] North Korea needs to concentrate on putting more effort into increasing weight on board," Kim said.
Ralph Cossa, the director of the Hawaii-based Pacific Forum, told VOA that another challenge facing North Korea is that it still must figure out how to make a nuclear weapon small enough to fit on a missile. He says this would require many more tests.
"This doesn't mean they have miniaturized [a nuclear weapon] that is capable now of being put on a rocket and launched at something and then being capable of hitting whatever it was launched at,"noted Cossa. "A number of additional skills and tests need to happen for something like that to be confirmed."
Michael McKinley, an Asian security expert at Australian National University, tells VOA that the size of the nuclear warhead is not the only issue limiting North Korea. He says even though it can fire a rocket into space, that does not mean it has figured out how to make it hit a target on Earth.
"Yes, it's up there, so it's an increase in their technological competence in North Korea," McKinley said. "There's no evidence at this stage that North Korea knows how to conduct the re-entry phase that would be needed if it were to target a foreign country."
McKinley said he does expect North Korea to achieve progress in these areas. He says that progress could begin with a third underground nuclear test, as well as repeated missile tests to ensure it has mastered all phases of the launch of an ICBM.
But many analysts, including McKinley, agree that even if North Korea were to achieve the ability to threaten America with a long-range ballistic missile, it would be unlikely to use it.
"If we take the really worst-case scenario at the moment - that North Korea can eventually put together a small amount of missiles capable of launching 6,000 - 8000 miles from home, the question then is, why would they want to do it? Any attempt, for example, to attack the United States means oblivion for North Korea," McKinley said.
Some analysts say North Korea's recent success means former U.S. Defense Secretary Robert Gates may have been right when he predicted two years ago that Pyongyang could develop a missile that could hit the continental U.S. by 2015.
But in any case, current defense secretary, Leon Panetta, told CNN on Wednesday he is "confident" the U.S. could stop an incoming missile from North Korea using America's "very strong missile defense system."
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