SEOUL -- Pyongyang surely can be said to have stepped over the line once it is confirmed that the suspected spy boat that played tag with the Japanese Coast Guard last month was indeed from North Korea. The incident has led Japanese Prime Minister Junichiro Koizumi and his administration to perform an overall review of its existing North Korea policy.

One bothering question, though: Is Japan missing something even bigger while investigating the latest event?

When the accident occurred, even an observer stuck in Seoul could make out traces of a familiar pattern. The five typical signs were there: secret entry; quick effort to escape; intensive resistance until the last minute, accompanied by gunshots; suicide attempts by agents; and absolute silence from Pyongyang. Any more questions?

Although this is just speculation, I bet those so-called spy boats were involved with trafficking drugs in Japan as this is one of North Korea's means of earning foreign currency.

There is, however, one thing that the Japanese media failed to cover. It was Dec. 18 when Japan's maritime authority spotted the unidentified ship near the Japanese coast and notified the Self-Defense Forces. Soon thereafter the Defense Agency found out that the ship was using a frequency band linked to North Korean authorities. But it was not until four days later that the Japanese Coast Guard set out to pursue the suspicious boat. What were Japanese marine units doing in the meantime? Waiting for the illegal ship to finish its trafficking or whatever and head back home?

Having declared that the coast guard's reaction to the incursion was fully justified, Koizumi is on his way to making a full revision of Japan's existing North Korea policy. As the leader of the Japanese rightist movement since the Sept. 11 terrorist attacks in the United States, perhaps Koizumi wasn't really bothered by the episode. In fact, it is likely to give his rightist policy added momentum. As the saying goes, he got a good slap exactly when he needed to cry.

Tokyo's marine operations were superb. Back in March 1999, North Korea pulled off a similar stunt and got away with it. This time Japan succeeded in surrounding the unidentified vessel with an Aegis battleship, 25 patrol boats and four jets -- leading to the destruction of the ship. As experienced South Korean Navy officers will tell you, such coordination, with multiple ships and planes, is anything but easy.

What bothers South Koreans is that Japan may have become caught up with cornering North Korea while missing the bigger picture. Frankly speaking, this is a good chance for Koizumi to try to solidify his rightist policy.

Instead of tinkering with security laws, the prime minister should be trying to re-establish a basic policy toward the Stalinist state -- whether to return to the anticommunist policy of the Cold War days, or press ahead with engagement. So far, all Tokyo has done is follow a step behind Washington's policy. That is both disturbing and incomprehensible.

As long as North Korea persists in its old ways, the number of spy-boat incidents will increase. It would be better if Koizumi left the latest brouhaha to the Defense Agency and ponder Japan's basic stance toward the North. The incursion was important, but at this point it pales in comparison to Japan's problem of lacking a clear North Korea policy.