Two weeks ago, I was in Seoul and wrote about South Korea’s 386 Generation. This anti-American, anti-Japanese, pro-communist generation is, as I see it, the half sibling of the New Left generation that dominated Japan in the 1970s, with its pro-communist, anti-American and anti-Japan-U.S. security alliance stance.

In Japan, this cohort is now retiring from the forefront, while in South Korea, the 386ers are still in their 50s and will dominate the country’s politics for two more decades. This is the main reason why I am ambivalent — neither optimistic nor pessimistic — about the future of Japan-South Korea relations.

When I mentioned this to a friend the other day, he immediately brought up the hypothesis about human history working in 70-year cycles. This theory posits that the dominant culture, philosophy or ideas of an era are created and then destroyed repeatedly in cycles of about 70 years. Over the course of 70-odd years — or four generations, each about 17 or 18 years long — cultures, philosophies and ideas are created, inherited, mature and eventually become obsolete and are rejected.