The Conservatives now have a simple choice - leave by hook, or by crook, or face annihilation

Boris Johnson is right: the Tories face extinction if Britain doesn’t leave the EU by Hallowe’en. Trust has evaporated: the Conservative Party’s only hope of survival is some sort of real, meaningful and visible Brexit by the end of October.

If our departure from the EU is delayed again, or if Eurosceptic voters believe that they are being fobbed off with a Brexit in Name Only, they won’t return to the party, and it will be toast. The rise of Nigel Farage’s Brexit Party has changed everything.

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We are therefore at a historic turning point, as the Peterborough by-election will doubtless confirm in the early hours of Friday morning. Thanks to Theresa May’s idiotic mismanagement, there are now four parties at around 20-something per cent in the national opinion polls. Small variations in support and turnout could lead to massively different electoral outcomes.

In such a world of radical unpredictability and volatility, the only certainty is that the Tories would be wiped out if a general election were held before Brexit: nobody knows how many seats the Lib Dems, Brexit Party and Labour would pick up, and which alliances would be possible. First past the post breaks down when confronted with extreme fragmentation.