ALBERT Einstein once called nationalism the measles of mankind, a quote so raw and yet so clever in its conception that is difficult to erase from your memory.

Of course, context is all, Einstein was talking of the dark national socialism of the Nazi Party in Germany, the racist terror it brought to Europe and the brutalisation of Jewish intellectuals like himself.

He was not talking about nations like Alegria or Angola that pursued their ­independence from the grip of colonising nations, nor the post-apartheid constitution of South Africa, which unravelled the ­racist segregation of the past, and he certainly didn’t mean the United States of America where he took the haven of citizenship in 1940.

When its used in the context of ­Scotland, the intent is to drain ­nationalism of all its progressive meanings. The irony is that the most virulent opponents of Scottish independence are people who are meshed in the very ideology they claim to despise.

Last week was a masterclass in the ­evasive ways of British nationalism. ­David Amess was callously killed in a church in Leigh-On-Sea. His murderer, Ali Harbi Ali, was described as British born with Somalian ancestry, leaving open the door of instant judgment. With no ­verifiable proof, the insinuation was that he must have connections with the Daesh-linked terrorist cell, Al-Shabaab.

As his “foreignness” was being ­highlighted, what was held back was the more everyday fact that Ali Harbi Ali had ­attended a Christian school in Purley, supported England at international football games and was not the sinister loner of terrorist fantasy but a relatively well-integrated young man. We may never know what took him to Leigh-on-Sea but ­British nationalism was already ­buoyantly ­convinced it was his Somalian ancestry.

The febrile tone of politics at the core of extreme British nationalism, and its favoured political project, Brexit, likes to play fast and loose with notions of ­Britishness. When Jo Cox was shot by the Brexit extremist Thomas Mair, he was never described as a British citizen of Scottish ancestry nor was his crime ­catalogued as domestic terrorism, nor was there any suggestion that it was his Britishness took him on the route to ­violence: extremism it seems is reserved for those that come from foreign lands.

Trite as it may seem, in the very week that Ali made his murderous journey to Leigh-on-Sea, Cameron Norrie won a ­tennis tournament at Indian Wells, ­California. Throughout the eulogising sports coverage, he was referred to ­simply as British and not more accurately as a South African of British ancestry. His ­father is Scottish and his mother is Welsh.

All nations love winners, which is why international sporting competitions are so popular, and why it is frequently the most tolerated form of outright nationalism. The Serbians love Novak Djokovic, the Swiss swell with pride that Roger Federer is one of their own, and of course, Andy Murray is periodically British and sometimes Scottish.

Beyond sport, British nationalism is powered by a desperate exceptionalism, the need to lead the world, to be the best and to be “Great Britain” is a theme that recurs across public discourse from Brexit debates to vaccination roll-out. Anything that challenges the God-given narrative of British success is unwelcome, no matter how important.

Our media has yet to be fully ­transparent about the much trumpeted success of the Oxford Astra-Zeneca vaccine. After cheering it around the stadium of science, it seems it has now fallen behind its key rivals Pfizer and Moderna. When South Africa suspended plans to inoculate its frontline health-care workers with Oxford Astra-Zeneca after its efficacy fell short in clinical trials, the silence from the British nationalist press was deafening.

What we know about British ­nationalism is that it positions itself as the cultural norm, the true centre of ­civilization in which everything else is a diversion or in flawed retreat. That is why the right of the political spectrum are so obsessed with immigration and the need to control the arrival of people from other parts of the world, even those in evident peril and stress.

David Amess’s death opened a fascinating curtain on that compromised ­democracy. What was praiseworthy about him was the sheer range of the ­parliamentarian’s interests. He was ­committed to raising awareness of ­endometriosis, a prominent ­supporter of animal welfare and, of course, a ­parliamentary siren for his constituency in Southend-on-Sea.

TELLINGLY, what has attracted next to no attention is that he was the parliamentarian that had shown the most ­outspoken support for Tamil nationalism, the ­aspiration of the Sri Lankan minority to create Eelam, an independent state to the north of the island.

Last week, Tamils from across the UK paid tribute to David Amess, and a group of young Tamil activists gathered to show their respect at College Green near the House of Commons.

Amess was a free-thinking member of the Conservative &Unionist Party who seemed more comfortable with economic and social conservatism than he was with unionism.

At the time of his death, a prominent Tamil website reported that Amess had called on the Sri Lankan government to account for the thousands of disappeared during and since the island’s bloody civil war. The online requiem carried words rarely heard about Conservative politicians: “He truly supported the inalienable right of Tamils to self-determination and the campaign to secure justice, peace, and a permanent solution for Tamils.”

The rights of nations to self-determination under UN mandate is a ­powerful argument in support of a Scottish ­independence referendum too, one that is not referenced enough by our ­politicians. I cannot understand why journalists do not challenge the most stubborn ­Unionists to square their stubborn ­opposition to a ­second referendum with the United ­Nations charter?

The murder of David Amess has been a rallying point for parliamentary democracy. But the same courtesies were not universally extended to Jo Cox when she was murdered by a British nationalist. It is not so long ago that Boris Johnson provoked gasps of disbelief in the Commons when he claimed that the best way to ­honour her would be to “get Brexit done”.

Brendan Cox, her husband, said at the time that he felt “a bit sick at Jo’s name being used in this way”. It was not the spirit of cross-bench camaraderie that Boris Johnson, a New York-born Briton, of Ottoman ancestry, was peddling last week.

Nor did it strike me as entirely plausible that MPs with hugely chequered histories of ugly British nationalism could align this new found camaraderie with their own past record. Mark Francois, the MP for Basildon, is a buffoon Brexiteer whose version of nationalism is a curiously old fashioned form of Bulldog Britain. He once said in parliament: “My father, Reginald Francois, was a D-Day veteran. He never submitted to bullying by any German, and neither will his son.” The ludicrous Francois used the death of his colleague to advocate David’s Law, a toughening of the Online Harms Bill. This was despite any evidence that the killer was motivated by online hate.

I cannot claim to have met David Amess nor do I share his views on Brexit nor the Christian fundamentalism that led him to oppose gay marriage, but I respect the fact that he had a curious mind and stood up for minority nations pursuing their right to self-determination.

Amess was a complex man with ­contradictory views and for that alone may he rest in peace.