Ask Labour members what their hopes are for a Jeremy Corbyn government and most will describe a modern parallel to Clement Attlee’s transformative administration of 1945 to 1951. Attlee rightly holds an iconic place in Labour history, but the 70th anniversary of Indian partition should serve to discourage us from romanticising his government. A wider re-examination of Attlee’s foreign affairs record shows that Corbyn is a Labour leader and potential prime minister without any historical precedent.

An array of culprits can be blamed for the horrors of partition, which caused as many as a million deaths and the creation of around 12 million refugees. Prominent among them is the British government of the time. Attlee’s Labour was not the innocent inheritor of a decomposing Raj. As Jawaharlal Nehru wrote from his prison cell in 1944: “The leaders of the British Labour Party have usually been the staunchest supporters of the existing order in India.” Central to that order was a policy of divide and rule, which proved a major factor in the subsequent violence.

As the historian Yasmin Khan has noted, the partition plan “imposed directly from London… was tragically unconcerned with human safety and popular protection”. The new borders were drawn up in a few short weeks by a British official on his first visit to India, using obsolete data and with no attempt made to visit the areas affected. Mass population transfer was neither predicted nor prepared for in the rush to dispose of a colonial possession that the UK was no longer able to exploit.

Attlee’s government was not the sole or even the primary author of the violence, but its role was real, its responsibility substantial. The catastrophe of 1947 and its enduring after-effects on the subcontinent are as much a part of that government’s legacy as the NHS. And, as events elsewhere show, its domestic achievements of the time and its role as an imperial power cannot be easily separated.

The relative economic stability required for the creation of the welfare state depended in part on various forms of imperial exploitation. In Malaya, commodity exports were the source of foreign exchange earnings that were crucial for the UK, given its precarious balance of payments, and Attlee’s government began a vicious counter-insurgency war to maintain British rule.

When Iran tried to wrest control of its oil from the Anglo-Iranian Oil Company (the precursor to BP), the Attlee government moved swiftly to retaliate. Nationalising key industries as part of a programme aimed at raising living standards was permissible only in Britain, not Tehran. Devastating sanctions were imposed on Iranian oil exports in the expectation that they would undermine the government and potentially lead to its overthrow. After the 1953 coup, backed by Attlee’s successor, Winston Churchill, and the US, the Labour governments of the 1960s and 1970s helped sustain the Shah’s dictatorial regime.

“Progressive” politics, far from being an impediment to British imperialism, has often served as its enabling ideology. We heard echoes of this last year when David Miliband opined: “If the world is increasingly divided between firefighters and arsonists, then Britain has for centuries been a firefighter.” We saw it in Tony Blair’s conviction that an Anglo-American invasion of Iraq would be some sort of humanitarian endeavour.

What sets Jeremy Corbyn apart from his predecessors are his roots in the anti-imperialist tradition, one in which the British empire is seen as one long criminal enterprise and the UK’s subsequent role in the world as disfigured by attempts to cling to its former status. The inclusion of the crimes of empire in the national curriculum, as proposed by Corbyn, would do much to detoxify the predominant sense of our national identity.

Never before has an anti-imperialist politician come so close to power in the West. Corbyn would not be able to rewrite Britain’s entire international posture but it would be fascinating to see what he could achieve.