Donald Trump’s visit to London will preoccupy the media for most of this week but it’s worth noting how the contest to elect a new Tory Prime Minister is unfolding.

After last week’s shadow boxing, the official contest is now being joined and with the contours of the campaign drawn.

Over the weekend Michael Gove and Matt Hancock both set out their Brexit positions with Gove conceding that another extension post-October 31st may be required and Hancock setting out in some detail how he proposed to deal with the Irish border issue. Both almost immediately incurred the wrath of ardent Tory Brexiteers who fear that allowing this to run into 2020 will only embolden Farage and the Brexit Party.

I expect Gove to emerge from this as the “stop Boris” and “stop no deal” candidate.

Meanwhile, Boris in his launch video this morning joined Dominic Raab and Esther McVey by reiterating that he intends to leave by October 31st.

So the dividing lines of the race could not be clearer, this contest will be fought on no deal v new extension unless the EU is willing to reopen negotiations this summer on the backstop which is unlikely but not impossible (there has been some murmuring regarding a three year time limit on backstop). The chances of this occurring might increase if Gove wins rather than Boris.

For the Gove camp if they win the sequencing will be as follows – a concerted attempt to engage with the EU followed in all likelihood by an appeal for another extension.

For Boris the trajectory is one that seemingly leads to a potential constitutional crisis and very possibly a general election.

As I argued in my last piece for Reaction, Boris will know that if he loses a vote of no confidence, probably in September within weeks of becoming PM, he cannot fight an autumn election exclusively on a no deal manifesto. Today in his Daily Telegraph column he sets out his plans to raise per pupil school funding and an increase in funding of further education. Revealingly he very specifically framed this to show disparity between funding of education in London and the rest of the country. His team will have noted the regional spread of Brexit Party votes so we can expect more announcements that play well outside the capital.

Most people write off the chances of a general election before the Tories deliver Brexit. Will Gove be able convince Tory Party members that he can ever deliver Brexit if he eschews no deal?

Or will the Tory selectorate trust Boris to deliver Brexit by Halloween even if it requires the enormous risk of a general election?

As they contemplate which way to turn in the coming weeks only one thing is certain – Nigel Farage will be surveying the scene from his eyrie and once more he has the Tory Party right where he wants them.

With every passing day the failure to pass the Withdrawal Agreement – and with it the chance to quell the nationalist populist insurgency – becomes more unsettling and its consequences more unpredictable.

I am reminded again of the words of the writer Bruno Macaes: “Brexit is not a technical negotiation between the UK and EU civil services, it is a cultural war to the end”.