LONDON (Reuters Breakingviews) - Before he was pitched from his plinth into Bristol’s harbour by protestors last summer, few in Britain had heard of Edward Colston. Yet the unceremonious dunking of the 17th century slave-trader’s statue forced a rare moment of self-questioning about the empire on which, as every Briton knows, “the sun never set”. As Sathnam Sanghera argues in his timely “Empireland: How Imperialism Has Shaped Modern Britain”, the collective amnesia over the nation’s often-dark colonial past underpins the jingoism that helped spawned policy disasters from Suez to Brexit. With luck, the book can be part of the solution. With Britain’s fishermen and small businesses counting the daily cost of leaving the European Union, Sanghera’s is no idle or remote psychoanalysis. In contrast to apartheid South Africa or Nazi Germany, Britain’s empire faced no dramatic denouement. To some minds it even limps on, more than four centuries after swashbuckling pioneers like Francis Drake, in tiny overseas territories like Gibraltar or the Falkland Islands. With no conclusion, there is little scope for the introspection and self-awareness that flowed from South Africa’s Truth and Reconciliation Commission, or Germany’s post-war “Vergangenheitsaufarbeitung”, which translates literally as “working through the past”. And Britain’s empire is quite a past to work through. In 200 meticulously sourced pages, Sanghera lays bare the role that the City of London and cities such as Bristol, Liverpool and Glasgow played in the transatlantic slave trade long before campaigners including William Wilberforce secured its abolition in 1833. Alongside the inconceivably large sums shipped from the periphery to the imperial centre – $45 trillion, in today’s money, drained from India between 1765 and 1938, according to Indian economist Utsa Patnaik – there are also intimate vignettes that help put a human face on a system that, as Sanghera notes, was about “dehumanising Black people on a super-industrial scale”. Sake Dean Mahomed, the first Indian to be published in English and the founder, in 1809, of Britain’s first curry restaurant, is a rare bright spot. The litany of abuse and atrocities will make tough reading for many Britons, from the genocide of indigenous Tasmanians in the 1830s to the concentration camps of the Boer War to the slaughter of hundreds of unarmed Indians in Amritsar in 1919. As a British-born Sikh, Sanghera’s shame at his ignorance of the last event is palpable and powerful. Prior to visiting Amritsar for a television documentary his only knowledge came from watching Richard Attenborough’s cinematic epic “Gandhi” on an aeroplane. Such an admission helps explain Britons’ lopsided understanding of their colonial past. Whereas three in four British children in 2011 studied the Battle of Hastings in 1066 or Great Fire of London in 1666, just one in 10 learned about the role of slavery in the Industrial Revolution or the colonisation of Africa. Against that backdrop, it is little wonder a 2014 YouGov poll showed 59% of Britons viewed the empire as “something to be proud of”. There can be fewer excuses for then-Prime Minister David Cameron, on a visit to Amritsar in 2013, declaring “there’s an enormous amount to be proud of in what the British empire did and was responsible for”. The flimsy historical knowledge has not stopped the tentacles of empire reaching into every nook of contemporary Britain, from its diet, to the global clout of the City of London, to the large proportion of Black and Asian workers in its National Health Service, built after World War Two with the help of labour invited from the colonies. As one chapter on immigration bluntly notes: “We are here because you were there.” Sanghera’s uncompromising assessment will certainly face disapproval, especially from those who regard criticism of empire as somehow unpatriotic. But a long, hard look at such a formative period is way overdue. The twin traumas of Brexit, with its related fantasy of reviving colonial links to replace trade with the EU, and the coronavirus pandemic, with its outsize impact on non-white Britons, are two pressing reasons to clamber onto the psychiatrist’s couch. “Empireland” provides another.