The Internet attacks are not isolated, but closely tied a broader North Korean military strategy, including its recent missile and nuclear weapons tests, say analysts.
"The cyber attacks are part of an asymmetric warfare strategy," says Nicholas Eberstadt, senior fellow at the American Enterprise Institute in Washington. "Part of an effective confrontation with the US war machine would be the ability to disable US information [systems]."
South Korea's National Intelligence Service "believes North Korea or its sympathizers" of having masterminded an Internet attack on the web sites of government agencies, including the office of the South Korean president and the foreign and defense ministries, according to Yonhap, the South Korean news agency.
Korea Communication Commission official Lee Myung-su said the computer virus had infected 18,000 personal computers and at least 11 South Korean government sites. US sites hit by the virus include the Treasury Department, Federal Trade Commission, and Secret Service. The Voice of America news services reports that its web site in South Korea has been out of commission for two days.
Mr. Eberstadt sees the cyber attacks as an integral component of North Korean testing of atomic devices on May 25 and in October 2006, as well as a recent flurry of tests of missiles that may one day be able to carry nuclear warheads.
"They may look like malicious cyber pranks," he says, "but the greater purpose is clear. When one looks at the nuclear chessboard, their security is integrally tied to this type of warfare." In order to launch a nuclear-tipped missile, he says, the North Koreans need a cyber warfare component in their arsenal.
Ultimately, he adds, "the nuclear weapons and cyber attacks have a purposed that go beyond cyber attacks." For example, he says, that North Korea wants to undermine the US-South Korean alliance, by making it seem "like a liability, rather than a benefit."
Kim Jong-il sighting
The Internet attacks represent a new area of confrontation in a period of uncertainty in North Korea dominated by rising concern about the health of North Korea's leader Kim Jong-il. At a memorial service marking
the 15th anniversary of the death of Kim's father, the long-ruling Kim Il-sung, Kim Jong-il was shown briefly on North Korean state TV walking with a slight limp. He reportedly suffered a stroke nearly a year ago. [Editor's note: The original version misidentified Kim Jong-il's father.]
Kim remained silent at the ceremony. Analysts speculate that Kim's main concern is arranging the succession of his youngest son, still in his 20s. At the same time, he must respond to pressures from his generals by promoting the "military first" policy – but apparently not to the point of risking another Korean War.
The attacks on South Korean websites suggest cyber warfare may be in lieu of attacks long predicted in the West or Yellow Sea or along the demilitarized zone between the two Koreas. A flurry of launches of short and mid-range missiles in the past week underline North Korean efforts to perfect their ability to zero in on targets but do not portend an imminent attack, in the view of analysts.
"Some of these missiles looked to have a real purpose, to demonstrate firing them all at once," says Mark Fitzpatrick, senior non-proliferation researcher at the Institute for International Strategic Studies in London. He notes, however, that the missile launches, including seven on July 4, "did not get much attention."
The same cannot be said about the cyber offensive. South Korea has one of the highest rates of Internet use in the world, making cyber attacks a particularly effective weapon.
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