Like just about every other truly prominent Conservative figure at the moment, everything Boris does is seen through the lens of his ambition to secure the leadership. Currently, the microscope is trained on his decision on the EU referendum: in the words of The Clash, should he stay or should he go? (Incidentally, a video of Boris singing that song at karaoke would stand a good chance of raising even more money than tonight’s Black and White Ball.)
It’s a speculation game that the Mayor is doing nothing at all to discourage. His latest Telegraph column is a particularly artful example of the EU fan dance which he likes to perform – leaving the audience with the titillating impression that they might have caught a glimpse of bare skin, without ever being quite certain that they did.
For all this flirtation with a Leave vote, Boris is not a natural Brexiteer. He grew up in the belly of the beast - for much of his youth, his father worked for the European Commission or served as an MEP - and many of his family and friends continue to pull him in a pro-EU direction.
But a by-product of this personal embedding in the Brussels machine is that he understands it a lot better than many other politicians. He knows its absurdities and its corrupt distortions, an insight sharpened by his time spent as the Telegraph’s correspondent out there during the turbulent Maastricht years. As a result, he has an ability to dissect its machinations in detail, subjecting the Prime Minister to a calculated torture. (He might be too good at this - as James Kirkup notes, if his intention is to extract concessions from Cameron before backing Remain then he is at risk of over-reaching and making it too painful for himself to backtrack later on.)
To a degree, his antics on this topic are better explained by his character than by his views. As my colleague Andrew Gimson notes in his biography, ‘he revelled in the chaos he caused’ by writing about the EU – in 2003 the man himself gleefully recounted his role in the Danes’ rejection of the Maastricht Treaty. Of his years covering the EU beat, he wrote:
‘Day after day, I would sit in my wonderful office in Brussels, looking out at the ponds, and I would marvel, in a horrified way, at the impact of news from Brussels. It was like chucking a crust into the water, and watching the fish boil and thrash to get it.’
That temptation to cause trouble for trouble’s sake, to observe and enjoy the effect of those liberally distributed crusts, has a powerful pull for the Mayor in addition to any strategic benefit he may perceive in doing so. The risk for him is that by stirring up speculation that he might support a Leave vote, the disappointment should he eventually back Remain will alienate people who might otherwise have supported him.