For the concrete examples, the problem is that the frame of public perception is very inadequate to probably objective risks or problems. How to force inadequate public frame to change? Is the only option to wait for a moment when the problems are very obvious? How can Cassandras do a better job?
If so, Winston Churchil must be a good example. He was ridiculled for anti-fascist concerns for many years, until the Nazi danger was plain obvious. He was then the obvious choice for leadership. And yeah, Churchil's rhetorics was outstanding.
The "diem" being what Pirsig calls "the cutting edge of Reality".
I am with Das Monde here, in that I see kairos as independent of Rhetoric.
It is the fleeting moment at which we ask our questions of Reality, answer them intuitively by making "Value Judgments", and describe our answers using Rhetoric.
As J A Wheeler said
Reality is defined by the questions you put to it
The difference between approaches was brought home forcibly to me by my current "Technocracy" Diary and observation of the huge difference between the approaches of the US - "Technocracy Incorporated" - and the European - "Network of European Technocrats".
Technocracy being a 1920's and 30's approach to Reality. "Any economic unit can emit money. The serious problem is to get it accepted" Hyman Minsky
A good example of a creative seizing of kairos is Gandhi's salt march of 1930. A protest of this sort was, I think, quite literally unimaginable to the British authorities. Its success came in part from this bold visionary stroke, partly from the way others spontaneously joined the march. In some very narrow sense it was a response to a tax on salt, yes. But it worked because it was more than a response. In creating a new reality of protest, the salt march refigured so many things: salt, taxes, colonialism, labor, gender (gathering salt was generally considered women's work), and so forth. (I'm relying, by the way, on my dim memory of a book I read about twenty years ago -- The Intimate Enemy by Ashis Nandy.)
But I forgot education, so, well...
Seriously, though, I was thinking of thesis-antithesis-synthesis.
A less salubrious (for me) example of kairos would be the UK fuel protests. Unexpected; used novel means; caught the national mood (of some--enough: those who felt they were being marginalised/ignored)...govt. frightened of a repeat; same thing threatened over other car issues: the car driver fought back!
Boo!
They used kairos.
Double boo!
My examples of possible kairos moments are two:
So...synthesis! And, yes, mushrooms! Mushrooms are good for kairos moments...
And my post is bent sideways...ach....! Don't fight forces, use them R. Buckminster Fuller.