Financial markets haven’t really reacted much to the escalation in tensions between the U.S. and North Korea, and some observers explain that it’s largely because in the worst-case scenario it’s impossible to guess the appropriate price for things like stocks and bonds.

"It’s hard to price a potentially extinction event (at least for much of the Korean peninsula)," is how Timothy Ash, a senior strategist at Bluebay Asset Management in London, puts it.

It’s a point also made by Mark Mobius, the Templeton Emerging Markets Group executive chairman and apostle for emerging-market investing.

He said in a May interview about the prospect of a North Korean nuclear conflict: "there’s nothing you can do about it -- if something breaks out, we’re all finished anyway.”

Maybe that’s why the worst day this year for the Kospi index of South Korean stocks was July 28, which was all about a global tech-stock retreat and nothing to do with geopolitics.