YOU can tell when British nationalist politicians have run out of plausible arguments against Scottish independence when they pull out the Margaret Curran defence.

During the 2014 independence referendum campaign, Margaret Curran, the then Labour shadow secretary of state for Scotland, argued that she was opposed to Scottish independence because of her son who lived in London, saying: "My son, for example, who went to university in England, I think I’d be uncomfortable with the thought that he's now a foreigner."

What she didn't add was that her parents were Irish, yet she apparently feels no discomfort about the fact that they too are "foreigners" – citizens of a country other than the UK. It appears that British nationalist discomfort about "foreigners" is highly selective.

Of course, in the real world, following Scottish independence, the offspring of Scots who are currently British citizens would also still be entitled to British citizenship on account of having parents who are British citizens, and so would not be "foreigners" even in the strictly technical sense of holding the passport of a different country. They would only lose this entitlement to British citizenship if the British Government decided to change its citizenship laws.

The government of an independent Scotland can no more strip British citizenship from a person who qualifies for it under the citizenship laws of the UK than it could remove American citizenship from a person who qualifies for it under American citizenship laws. The question of citizenship is decided by the laws of the state conferring the citizenship, no one else.

The offspring of Scottish citizens who live in England would also be entitled to Scottish citizenship and to Scottish passports following independence. So no British citizen living in Scotland is going to find that Scottish independence makes their children or grandchildren in England into "foreigners" following Scottish independence.

However, even if it were the case that Scottish independence meant that the children of Scots in England were now "foreigners" in the strictly technical sense of holding a different passport from that of their relatives in Scotland, so what? An independent Scotland would remain a part of the Common Travel Area along with the rest of the UK, the Republic of Ireland, the Isle of Man and the Channel Islands. Residency rights and the right to work or settle throughout the islands of Britain and Ireland will remain unaffected.

The latest desperate British nationalist to cite having family in England as a reason to oppose Scottish independence is the Scottish Conservative MSP Stephen Kerr who said during an episode of Debate Night on BBC Scotland that he was against what he called "the break up of these islands" because the Union "is the representation of things to do with kith and kin". He added that three out of his four children and nine out of his 11 grandchildren live in England.

Mind you, if I was unfortunate enough to be related to Stephen Kerr, I'd want to live as far away as possible from him too. The phrase "kith and kin" first entered British political discourse in the 1950s, when immigration into the UK from Commonwealth countries was becoming significant. The phrase carries unfortunate racist overtones.

According to a study of the racism inherent in British immigration policy in the 1950s carried out by researchers at Warwick University: "Whilst wishing to prevent Black British subjects from entering the UK, the Cabinet was concerned to preserve the right of white 'kith and kin' in the Dominions and to free entry."

In Kerr's remarks yet again we see the British nationalist xenophobic terror of "foreigners". It appears to be founded upon the decidedly peculiar belief that that quality of your love for and the nature of your relationship with your closest relatives is determined by and predicated on their citizenship status. If that is indeed true, it is not an argument against Scottish independence, it is merely proof that you are desperately in need of family counselling and therapy and need to grow up.

The emotional and psychological shortcomings of Stephen Kerr are not a reason not to have Scottish independence. The xenophobia of British nationalism most certainly is a reason for Scotland to escape its malign influence.

This piece is an extract from today’s REAL Scottish Politics newsletter, which is emailed out at 7pm every weekday with a round-up of the day's top stories and exclusive analysis from the Wee Ginger Dug.

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