A blimp depicting Boris Johnson hovers near a statue of Winston Churchill.Simon Dawson / Reuters

For more than three years, the world has watched Britain attempt to act on the result of its 2016 referendum and leave the European Union. Yet while the causes of the Brexit vote were complex, the causes of the catastrophic handling of the Brexit process might be familiar to anyone versed in imperial and postimperial history.

They stem from what appears to be a belief in British exceptionalism: the idea that Britain is inherently different from, and superior to, other nations and empires.

Margaret Thatcher asserted British exceptionalism with regard to the EU in a 1988 speech, and each of the past three prime ministers has approached the EU from that standpoint—believing that Britain deserves preferential treatment and more-than-equal status.

They have all also believed in their own personal exceptionalism. David Cameron believed he could win the referendum and thereby head off the electoral threat to his party from the right. He did not. Theresa May believed she could turn a narrow 52–48 vote in favor of leaving into a mandate for a “hard Brexit” in which Britain got everything it wanted and gave up nothing. She did not. Now Boris Johnson is voluntarily manufacturing a crisis over no deal—in which Britain would leave the EU without any agreement on the rules and regulations governing how it would trade and work with the bloc—that could send damaging shock waves through Britain, Ireland, and the rest of the EU.

There has been much discussion of the roles of history and memory in relation to Brexit. It may be easy to overstate a simplistic, literalist connection between the empire—imagined as glorious, and unjustly lost—and the impulse to leave the EU. Yet it is hard to avoid the sense that embedded in Brexit is a form of “Make Britain great again.” Sharper parallels are perhaps drawn between Britain’s collective recollection of its part in World War II, heavily mythologized as the moment it stood alone against Adolf Hitler, and the attitude of Brexit supporters to the isolation and hardship Brexit may bring.

While the myths constructed around the history of empire and World War II reinforce British exceptionalism, they are contradictory. The first casts Britain as a superpower; the second as a lone, plucky underdog. This dissonance is not new, nor is it unique to the Brexit process. It has helped produce disasters on an international scale before. The Suez crisis—during which Britain was neither able to take control of the Suez Canal, nor able to oust Egypt’s anti-imperialist leader, Gamal Abdel Nasser—is often cited as a precursor.

Brexit is a public withdrawal from a voluntary union; Suez was a covert invasion of a sovereign state. They are wholly different. Yet there is a familiarity to the grand aspirations undercut by slapdash and delusional strategic planning; to the frantic rush to act, even as it becomes clear that most or all of the options are damaging; to leaders fixated on a path that many can see will probably end badly.

In general, Britain remembers Suez as a blip in what is widely viewed as a mostly well-intentioned and competent imperial policy. Far from ending British exceptionalism, the disaster has been used to reinforce it. Suez can be framed as a unique aberration if it is blamed on what is erroneously held to have been a betrayal by the United States, and on the folly of one man, the physically and mentally exhausted Prime Minister Anthony Eden. That heads off more troubling questions about whether there were deeper problems with cabinet decision making, military advice, foreign policy, the political culture as a whole, and even the nation’s understanding of itself.

The historian Kim A. Wagner has made a similar argument about the Amritsar Massacre of 1919. Winston Churchill denounced that event—in which imperial forces fired on Indian civilians in an enclosed space, killing hundreds—as “without precedent or parallel in the modern history of the British Empire” and “absolutely foreign to the British way of doing things.” Churchill, who was a strong believer in empire, had not suddenly become a critic. As Wagner points out in his book Amritsar 1919: An Empire of Fear and the Making of a Massacre, Churchill’s speech “was, on the contrary, an elaborate act of deflection and a staunch attempt to reassert the moral legitimacy of the British Empire.” Just months later, Churchill was part of the cabinet that deployed the Black and Tans, temporary constables who gained a reputation for violence against civilians in Ireland.

Exceptionalism is again visible in what was by most metrics a far bigger disaster than Suez or Amritsar: the partition of India and Pakistan, which left between 1 and 2 million people dead, created 10 million to 20 million refugees, and established a hostile relationship between successor states that threatens global security to this day.

The last British viceroy of India, Lord Mountbatten, has been blamed ever since for speeding Britain’s exit deadline up. What he achieved by that was to ensure that most of the fallout did not happen on Britain’s watch. Internationally, many newspapers reported Indian and Pakistani independence alongside photographs of Mountbatten and British officials applauding the raising of new flags. (Mountbatten had all British flags removed in advance, thus avoiding embarrassing images of newly independent peoples cheering them being pulled down.)

Only in the days and weeks after partition did the shocking reports of death and destruction ramp up, and so British exceptionalism was able to remain unscathed. The British could sigh sadly at the appalling outcome, and murmur “après nous, le déluge.” The writer Pankaj Mishra has described a “malign incompetence” common to Mountbatten and the Brexiteers. His point rings true, but the critique cannot be limited to a few individuals, or it risks again letting the system itself off the hook. Why do British politics, society, and culture produce such individuals, promote them, and reward them? Only so many similar results of this system can be dismissed as aberrations before it begins to seem as if they might not be aberrations at all.

A British leadership that wanted to deliver Brexit safely and was not in thrall to exceptionalism might have learned from past mistakes. Suez might have taught it to prefer reality over fantasy, compromise and conciliation over arrogance and vaingloriousness. Partition might have taught it to respect and understand complexity rather than oversimplify difficult problems, to make a plan before setting tight deadlines. Both might have taught it that you should never, ever imagine you’ve had enough of experts.

But to learn from mistakes you must confront them, and exceptionalism means you never do. Successes may be evidence of Britain’s greatness, but failures are inherently un-British. It is worth noting, too, that exceptionalism does not affect only those who support Brexit. As the historian Robert Saunders has pointed out, “The idea that Britain should lead the EU—widely deployed [by campaigners who supported staying in the EU] in 2016—has as strong an imperial heritage as the aspiration to leave it.” What would be exceptional about meekly accepting equal status with 27 others?

Brexit is exposing flaws in the British political system and culture, but they are not new. Exceptionalist thinking has long helped insulate that system from the criticism and reform it needs.

For advocates and critics of Brexit alike, it may be tempting to imagine a golden age in which Britain was competent, reliable, stable, and sensible. Looking at its history, though, if it turns out to be none of those things, we shouldn’t be surprised.

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