TOKYO When North Korea announced on June 23 that it had successfully test-fired a Musudan intermediate-range ballistic missile the previous day, Pyongyang's aim was not just to demonstrate its improved weapons capabilities. The regime is hoping to drive a wedge between Japan and the U.S. and between South Korea and the U.S. by neutralizing these three countries' network of missile defenses.
North Korea has test-fired Musudan missiles a total of six times since April 15, including twice on June 22. The sixth was its first successful attempt. It is believed the missile reached an altitude of about 1,000km, temporarily leaving the Earth's atmosphere, and that it traveled about 400km before landing in the Sea of Japan.
It is difficult to interpret the results of the latest tests. Usually, if a missile test fails, the cause of the failure is analyzed in depth and another test conducted after necessary improvements are made. But because North Korea went ahead with the sixth launch mere hours after the fifth one, it could be argued that the success was a fluke and that the Musudan remains essentially unreliable.
But even so, if the sixth missile indeed landed in the sea with its warhead intact, it means that North Korea has overcome the last hurdle in the development of nuclear missiles: It now has the technology to protect nuclear warheads from the high heat of atmospheric reentry. It is a development that cannot be ignored.
Generally speaking, there are four ways of countering a nuclear attack: 1) deter an attack by setting up a system for retaliatory action; 2) preemptively destroy a missile before it is launched; 3) intercept a missile midflight with a missile defense system; and 4) minimize the death toll of an attack by building nuclear shelters.
To neutralize these countermeasures, North Korea has significantly reduced the risk of its missiles being destroyed in preemptive strikes by deploying mobile missiles, such as the Nodong and the Musudan, and its latest test launch could indicate that it can now head off missile interceptors.
The Musudan has an estimated range of about 3,000-4,000km, much longer than Nodong's 1,300km. By launching it into a trajectory about 400km higher than usual, the Musudan fired on June 22 not only traveled much farther, it also attained a dramatically faster falling speed.
"It would make it difficult even for Japan-U.S. missile defense systems to intercept these missiles," a person involved in Japanese security told this writer in spring, before North Korea started test-firing the Musudan. The successful launch on June 22 makes such concerns more real.
The U.S. relies on its nuclear arsenal to deter an attack and ensure that its homeland, its forces stationed overseas and its allies are safe from attack. But there is no guarantee that North Korea will heed this deterrence. If Pyongyang were to make a surprise strike with the Musudan on any of the U.S. military bases in Japan -- such as Yokota Air Base, the headquarters of U.S. forces in Japan, Kadena Air Base in Okinawa or Yokosuka, a home port for aircraft carriers -- the devastation would be immeasurable. Such an attack would not only destroy the base, it would cause numerous casualties, among both U.S. soldiers who could not get to a shelter on the base in time and local residents who have no such shelter in the first place.
There is also the chance of North Korea targeting not only a U.S. military base but also a major Japanese city. Even if the U.S. retaliated with several nuclear strikes and the Kim Jong Un regime collapsed, it would do nothing to change the fact that thousands had died in the initial attack.
With its latest missile launches, Pyongyang's message for the U.S. is that if America intervenes when North Korea tries to reunite with South Korea by force, U.S. military bases in Japan will be targeted for nuclear attack. The message for Japan is that if Japan helps U.S. and South Korean forces in the event of a major military confrontation on the Korean Peninsula, a nuclear missile will be launched against a major Japanese city.
Following the June 22 launches, U.S. Secretary of Defense Ashton Carter expressed his intention to further upgrade the country's missile defense systems.
It remains unclear, however, whether such improvement will prove effective in containing the threat posed by the Musudan. Japan has made huge investment in missile defense systems, but neither this nor the U.S. "nuclear umbrella" are enough protect the Japanese population. A more comprehensive approach, along the lines of the one South Korea has already adopted, is needed. This includes building shelters for those who live near military bases or in major cities and conducting emergency drills simulating an attack.