They may have triumphed in politics, but in academia, Brexiters are an embattled minority. Perhaps the most combative of their tribunes is the emeritus professor of history at Cambridge, Robert Tombs. Beyond the innate value of dissent, Tombs's own position is also intrinsically interesting. As a brilliant historian of 19th-century France, he can hardly be written off as a Little Englander. As a French citizen by marriage, he presumably continues to enjoy the benefits of EU citizenship as well, so he has less skin in the game than most.
A short, punchy, eloquent statement from such a distinguished historian on the case for the kind of very hard Brexit that has now become a reality raises hopes for some genuine illumination. But The Sovereign Isle will, for varying reasons, disappoint both many of Tombs's fellow Brexiters and anyone looking for a cogent statement of what this great disruption means for the economic and political future of the UK.
In the first instance, Tombs is too true to his profession to peddle the Brexiter myth that continued membership of the EU was incompatible with the historic identity of "our island nation". He knows that other European countries have "histories of struggles for independence and democracy at least as proud as our own, but which so far they find compatible - if with some strain - with European integration".
There is an admirable lack of determinism in Tombs's framing of Britain's relations with Europe: "Is there a pattern in this long and complex story of the relations between our offshore islands and the Continent? . It is tempting to say that the pattern is an absence of pattern." So no Agincourt and no Dunkirk. A lot of his potential readers will be disheartened to find that "those who claim that history is on their side are abusing it".
The price to be paid for this honesty, though, is that for most of the book Tombs is writing less as a scrupulous historical scholar and more as a political polemicist. The difficulty is that the two sides of his persona never really cohere. He makes, for example, a good historical case that the declinist narrative of the 1950s and 60s that led Britain to see membership of the common market as its only route to salvation was exaggerated. But he then bases most of the book on a very similar trope of Europe as "a declining Continent". What the historian challenges, the polemicist embraces.
The contradictions multiply. Tombs is deeply committed to the two central and intertwined propositions that have propelled Britain towards its deeply uncertain fate as a semi-detached adjunct to that continent. The first is that sovereignty is an absolute concept; it "can be given up, but not shared". The second is that "there was only one meaningful Brexit, which was to leave the Single Market, the Customs Union and the jurisdiction of the European Court of Justice".
Where then does this indivisible sovereignty lie? Tombs rejects the notion that it belongs with the elected parliament in Westminster. He also disputes the right of the supreme court to find illegal Boris Johnson's attempt to prorogue that parliament in 2019. So, sovereignty can lie only with the people and can be expressed only by their vote in a referendum.
But if the referendum is the sacred moment of the exercise of sovereignty, why were the sovereign people not told in 2016 that, as Tombs insists, the only form of Brexit they were going to get was one of the most extreme imaginable? How can sovereign decisions be made in ignorance of their meaning?
Equally, Tombs, like all Brexiters, expresses his contempt for the second referendum on the Lisbon treaty held in Ireland in 2009 after the first one was defeated. He claims that the first vote was "overruled". It wasn't. A democratically elected Irish government negotiated changes and a free electorate endorsed the treaty by a two-to-one majority. In doing so, Tombs claimed, the Irish had "given up their sovereignty". Apparently, a referendum is a sovereign act only when the result is one of which Tombs approves.
There is, moreover, an underlying tension in the idea of "the people" in an explicitly multinational state like the UK. Tombs gets over it (as he gets over other problems for the idea of exclusive sovereignty, like the climate crisis) by refusing to recognise it. Even his most basic term of reference is evasive. His title speaks of an "isle", singular. In the text, this slips awkwardly into "our islands". But by "our", he really means England's: all his key points of reference are English.
Small wonder that Tombs is confident enough to assert that "Brexit should not be a threat to the Union". He says Scotland will not leave because of economics. Maybe so, but this is an odd argument in a book that insists that sovereignty is more important than anything else.
Likewise, he claims that a United Ireland is "impractical" because the Republic's "living standards were 10 to 20% lower than in the North" in 2015. I checked the academic paper he cites for this figure. It says: "People in Northern Ireland were approximately 4% better off than people in Ireland" in 2016, and stresses that the gap has been narrowing very rapidly. Tombs the historian would not be so cavalier with sources as his polemical doppelganger seems to be.
The biggest contradiction of all is that, on the one hand, he argues that the future lies with the nation state and the sense of rootedness in place that makes democratic engagement possible. Fair enough - except that, on the other hand, he ends up suggesting that place doesn't really matter anymore: "Geography comes before history. But for centuries we have been loosening the bonds of time and distance. Place has become less important." If that is so, how can the old idea of pure sovereignty not need to be rethought?
Tombs doesn't ask. The Sovereign Isle is much less a work of analysis than it is an expression of faith. It recites, albeit in mellow tones, the familiar Apostle's Creed of Brexit: the referendum was won by the votes of "the excluded, the unemployed and simply the less well off" (no mention of the very wealthy southerners who voted for it); the EU is doomed; the Irish border question was probably got up by the French; there is no economic downside; the "Anglosphere" and the Commonwealth will replace the European connection.
Even recited so suavely, these doctrines are no more convincing to the unbeliever. Given Tombs's genuine intellectual standing, this is probably as good as it gets. Brexit, like it or not, is a fact, and it would be a great service to us all if someone could set out a half-convincing case for why it makes sense. Since Tombs can't, maybe nobody can.
. The Sovereign Isle: Britain In and Out of Europe is published by Allen Lane (£16.99). To order a copy go to guardianbookshop.com. Delivery charges may apply.