Ps John, the single use was already demonstrated, whichever happened first, Hiroshima or Nagaski, but still the second use occurred, both against a country which could not respond.
What lesson was learned from that, given where we are now?
To me, what happened was simply a demo of how effective the weapon of mass destruction of nuclear weapons is.
If we want to kill and terrorise millions of people into submission, there is no better way.
We need a miracle to avoid armaggedon breaking out over Ukraine, rapidly spreading to the world.
Ai is the miracle, as far as I can see.