TOKYO -- Imagine an organization -- whether it be a government or a business -- that faces a serious issue. If its leader insists that there is still a good chance that the issue will be settled somehow, despite the fact that the current approach has clearly become bogged down, that attitude is insincere -- and even dangerous. This attitude would cause delays in taking a second-best policy, and it would also make the situation worse.

The present state of the North Korea nuclear issue puts nations concerned in just such a situation. From May through October, Pyongyang has fired new types of missiles. Meanwhile, administrative-level talks between the U.S. and North Korea in Stockholm on Oct. 5 ended without any progress.

It is time for countries concerned to coolly acknowledge this reality and admit to the failure of the approach taken toward North Korea thus far. Only after doing that can they seriously think of new possible steps for breaking the impasse.

Even though the media should refrain from fanning threats and stirring public unease when discussing national security issues, it is hard to deny that North Korea's nuclear threats have crossed a perilous line.

There are two reasons to conclude this. First, North Korea has apparently achieved the miniaturization of nuclear warheads and now has nuclear missiles that can reach Japan and South Korea. The North has an estimated 20 to 30 nuclear warheads, according to a study by the Stockholm International Peace Research Institute. The country is believed to have succeeded in making warheads small enough to be mounted on missiles.

North Korea appears to have succeeded in miniaturizing its nuclear warheads and now has nuclear missiles that can reach South Korea and Japan. © Reuters

The Japanese government's annual Defense of Japan report released in late September acknowledged for the first time that Pyongyang has "already successfully miniaturized nuclear weapons."

This blunt recognition of Pyongyang's nuclear capabilities follows last year's report by the Japanese government in which it acknowledged the possibility that North Korea had realized miniaturization. According to sources close to the Japanese government, the most recent assessment is based on calculations of the number of years that the world's nuclear-armed nations -- including the U.S., China, Russia, India and Pakistan -- took to miniaturize warheads and the number of nuclear tests they conducted.

It seems unthinkable, however, that Tokyo reached such an important conclusion, and published it in an official defense report, based simply on analogy. The sources must have gained intelligence -- through information exchange with the U.S. and other friendly countries -- that endorses their hypothesis.

If this is the case, Japan and South Korea are likely to be already within the range of North Korea's nuclear missiles. Katsutoshi Kawano, who until the end of March was chief of the Japan Self-Defense Forces' joint staff, the top uniformed officer of Japan' armed forces, said: "If North Korea has succeeded in miniaturizing nuclear warheads, there is a great likelihood that the country has already deployed nuclear missiles. The SDF, for its part, must think of how to respond to it at least based on that premise."

The second reason why the North's nuclear threats have crossed a critical line is that the reclusive country has developed different types of short- and intermediate-range missiles -- some of them believed capable of carrying nuclear warheads -- which could breach the Japanese and South Korean missile defense networks.

North Korean leader Kim Jong Un smiles as he oversees missile testing at an unidentified location in North Korea, in this undated image provided by the Korean Central News Agency on Aug. 7. © Reuters

Among them are ballistic missiles similar to Russia's Iskander, on which Pyongyang carried out test launches four times between May and September. These missiles follow relatively level trajectories at an altitude of about 50 km. Near the end of its flight, the missile performs a steep, spinning climb before falling at an angle of 80 to 90 degrees. Any missile employing such irregular movements would be hard for Japan to counter.

Japan currently has two missile defense systems. One is the Standard Missile-3 (SM-3) system, which is loaded on Aegis-equipped vessels. The other is the Patriot Advanced Capability-3 (PAC-3) surface-to-air missile system.

The SM-3 system is designed only for interception above the Earth's atmosphere, which means it cannot be a workable defense against Iskander-type missiles. Although Japan also plans to deploy the Aegis Ashore land-based missile defense batteries, these, too, share this performance limitation.

Junichi Nishiyama, senior research fellow at the Institute for Future Engineering and an expert on defense technology, said: "The SM-3, used in a missile defense system loaded on Aegis ships and in the Aegis Ashore system, is designed to counter an attack in outer space where there is no air resistance, making it unable to shoot down ballistic missiles flying in the Earth's atmosphere."

Although the PAC-3 is workable within the atmosphere, its rate of success in intercepting is lower on missiles with irregular trajectories, and the system can only cover a radius of 20 km. Moreover, even if the system manages to intercept a target missile, nuclear contamination would still be inevitable.

A team of Japan Self-Defense Force troops stands by a Pac-3 missile interceptor battery at the Defense Ministry in Tokyo on Feb. 7. © Reuters

South Korea's missile defense system seems to have similar limitations. As such, Washington is concerned -- and not just for Japan and South Korea, but also for U.S. armed forces stationed in the two Asian allies.

When U.S. Secretary of State Mike Pompeo has met with Japanese government officials, he has repeatedly expressed his concerns about the seriousness of Pyongyang's recent missile tests. He is said to find it difficult to openly censure the North Korean regime because U.S. President Donald Trump, who wants to keep U.S.-North Korea talks from falling apart, has repeatedly expressed his iew that the test are tolerable.

What, then, should Japan do? Some experts have floated the idea of letting Japan have capability to attack overseas missile bases. But many of North Korea's missile launchpads are mobile. "As they hide themselves soon after rockets are fired, it is difficult to track them and perform pinpoint attacks," a senior SDF official said. There is a lively debate to be had over the conditions under which Japan should be allowed to make preemptive attacks.

Given these circumstances, Japan's minimum duty is to maintain international economic sanctions against North Korea, which will help keep the pressure on Pyongyang to limit its nuclear buildup. Also, in order to never let North Korea use nuclear missiles, Japan and South Korea should join with the U.S. to heighten their nuclear deterrents. These countries must continuously explore new technological ways to counter missile attacks.

The international community cannot give up the hope that the Washington-Pyongyang talks can succeed in the denuclearization of North Korea. However, it has become clear that this path will be extremely hard. For the moment, countries concerned must work to contain North Korea's nuclear threats.