The war at the time seemed to be what Churchill might have said to be at "the end of the beginning or the beginning of the end" making the statement quite inflammatory and in total diametric opposition to the British government point of view, for sure.
I wonder what if any consequences he might have been subjected to speaking with such animus towards the country that literally saved the limey bastards from certain conquest.
It just seems to me that the egregiously prejudicial perspective otherwise known as historical revisionism began even before the war seemed winnable, I suppose.
There was a subculture in the UK who claimed the US stayed out of the war long enough to allow Britain to lose her empire. The claim that we coerced Japan into attacking us fits into the same sort of thinking...
There will certainly be several now "definitive" Pearl Harbor histories as time passes.
In the US, the period between WWI and WWII was often thought of as the "golden" age of said historical revisionism.
On Churchill, see Reynold's In Command of History for another aspect of those six volumes. Ismay was the lead filter then.