I think this piece gets it exactly right: Hammond's interview lends credence to the view held by many at the time, including me, that the Oct 2016 speech changed things a lot, and probably wasn't understood adequately by the person delivering it. https://twitter.com/davidallengreen/status/1356907215819599873
I recall I was really startled by it. I'd assumed up to that point that we'd muddle through to a soft Brexit, which nobody would love but most people could live with. Seeing May suddenly lurch to the ERG position was a real shock.
(Though I note the warning of Ivan Rogers and others that a Norway-type solution wouldn't really be viable for the UK long term and am not going to dare to attempt to contradict that.)
I'd add one further point. May/Timothy kicking the stool away from underneath any sort of compromise / soft Brexit also re-lit the flame of Remain, and made possible the hardline remain movement we later saw.
The stakes had been raised so high, and an extreme, hard Brexit made so likely, that fighting to remain seemed both legitimate and essential to many who would probably otherwise have gone along with a Norway-style outcome.
So when articles are written blaming the Remain movement for stupidly going for broke and aiming for a Norway type settlement or similar, my response is to look to October 2016, when the debate was polarised and the prospect of compromise killed off.
And that's what brought us to the events of November and December 2019, which I agree with the article was the second of the two crucial periods when things could have gone differently.
My final reflection is that the rise to office of a Prime Minister who was simply not competent to understand the obvious policy implications of what she was announcing is a firm indicator that our politics & probably constitution are in trouble. Just in case anyone doubted that.
(The subsequent rise to office of a Prime Minister manifestly unfit to do the job is a confirmation we could have done without, but that also has its roots in October 2016, when from a position of strength May put her own permiership in an untenable position.)
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