A nuclear test that North Korea conducted in the northeastern part of the country on Sept. 9 poses a serious threat to Japan's security.
Pyongyang asserts that it was successful in conducting an "explosion test for the judgment of the power of a nuclear warhead."
It was the fifth nuclear test that North Korea has conducted since 2006, and this year's second test following one in January. This was the first time that the North had conducted multiple nuclear tests in a single year, and the scale of the explosion in the latest test is viewed as the largest one the country has conducted.
North Korea has also launched 21 missiles, such as Rodong and Musudan medium-range ballistic missiles and a submarine-launched ballistic missile, since the beginning of this year -- far more than the several per year it tested until 2015.
Since North Korea now poses a more serious threat to the international community, Japan should place higher priority on its response to North Korea's nuclear and missile issues.
North Korean leader Kim Jong Un had issued an order to conduct a nuclear warhead explosion test and test-fire missiles capable of carrying nuclear warheads at an early date. The order reported by state-owned news media in the country this past March has apparently led to the latest nuclear test and a series of missile launches.
Close attention has been focused on the progress North Korea has made in its efforts to downsize nuclear warheads so that they can be carried by missiles. It is obvious that steady progress has been made in North Korea's development of small nuclear warheads, even though it is still impossible to make a final judgment.
North Korea's possession of nuclear missiles would go against the interests of all of its neighboring countries. As such, the international community should strengthen its alliance to prevent a potential nightmare from becoming a reality.
Still, there are limits to what the international community can do to address the issue. The international community has already imposed unprecedentedly severe economic sanctions on Pyongyang. Japan, the United States and South Korea have little room for imposing effective sanctions any further. Even though China is strongly opposed to North Korea developing nuclear arms, Beijing does not want the Kim Jong Un regime to collapse.
North Korea is fully aware that the international community is in a gridlock in further stepping up its sanctions against the country. North Korea notified China, the United States and other countries before conducting its first, second and third nuclear tests but this year it appears to have stopped alerting even China prior to such tests.
Kim has indicated that North Korea is developing nuclear weapons based on the lessons the country has learned from Libya's abandonment of its nuclear program. The Muammar Gaddafi regime abandoned its nuclear development program through its negotiations with the United States and Britain, but the regime collapsed because of military interventions by Europe and the U.S. during a civil war that broke out in 2011.
Therefore, Kim believes that his country cannot abandon its nuclear weapons development. North Korea won't stop developing nuclear arms unless its leader changed this belief.
When Pyongyang's nuclear development emerged as a major international problem in the early 1990s, the United States seriously considered launching military attacks on North Korea. It is necessary for the international community to be fully aware that the program poses a far more serious threat now than in the early 1990s when the country's nuclear technology was still at an elementary stage.
North Korea has already deployed more than 200 Rodong missiles that have almost all parts of Japan within their range. Japan is among the countries that are exposed to the most serious threat posed by North Korea's reckless acts. Japan must proactively make diplomatic efforts to establish a coalition against Pyongyang's nuclear and missile programs.
In particular, it is important for Japan and other members of the international community to urge China to agree on international sanctions on Pyongyang as well as to use its influence on North Korea to persuade the country to exercise self-restraint.
China imposed sanctions on North Korea based on a U.N. Security Council resolution adopted in March this year, but it reportedly has little impact on bilateral trade between the two countries. It is necessary to encourage China to fulfill its responsibility as a major power to contribute to regional stability.
It is more important to urge the United States to use its influence to address the issue. North Korea regards the United States as its sole negotiating partner over its nuclear issue, and has demanded repeatedly that Washington guarantee the security of Pyongyang's regime.
The U.S. government of President Barack Obama has adopted a policy of "strategic patience," or waiting until Pyongyang changes its attitude toward the nuclear issue.
The United States should not show a reconciliatory attitude toward or accept a deal with a country that threatens the international community. In this sense, the Obama administration's policy is understandable. But there is no denying that the policy of "strategic patience" has ended up allowing Pyongyang to go ahead with its nuclear development.
North Korea conducted four of its five nuclear tests after Obama took office. Therefore, the Obama government should take action to prevent North Korea's provocative acts from escalating.
Pyongyang is also developing inter-continental ballistic missiles. North Korea is feared to advance the technological levels of its missiles while the next U.S. president, who will be elected in November, is still in office. Therefore, the issue will certainly pose a serious threat to the security of the United States.
Japan should join hands with South Korea, with which it shares the same interests, in strongly urging the next U.S. government to seriously deal with North Korea's problems.
It is a serious diplomatic challenge for Japan to contain North Korea's nuclear weapons program. Tokyo should strengthen its cooperation with Washington and Seoul in reinforcing the international coalition against Pyongyang's nuclear and missile programs.