Two months have passed since the top leaders of the United States and North Korea met in Singapore. Some Korea hands in Tokyo were so optimistic about the outcome of the U.S.-North Korea negotiations that they even called the June 12 summit a great first step for peace in Northeast Asia.

Although few people at that time were confident enough to openly challenge their groundless sanguinity, it may be still premature and unfair to conclude, like a Monday morning quarterback, that they were wrong. Nonetheless, I was truly appalled last week when I heard one of them say: "Strike while the iron is hot."

I do not know when this presumably British proverb started to be commonly used in Japan. In English, the famous saying means "to take advantage of an opportunity as soon as it exists, in case the opportunity goes away and does not return." The Korea expert suggested that Japan must change its policy vis-a-vis North Korea.