Boyd Tonkin: UK visa policy humiliates creative visitors who should be friends. It's a disgrace

If you ran the intelligence service of an unfriendly power - Iran, perhaps, or even China – and wished to discredit Britain in the eyes of current opinion-formers and future leaders overseas, how might you set about it? Here's a cunning plan. Have an assortment of high-prestige events – festivals, conferences, symposia – invite rising stars in literature, the arts and academia to Britain. Then infiltrate the UK visa-issuing offices in their home regions so that these influential voices found themselves disbelieved, mocked and grossly insulted by outsourced agents of the British state.

Deny them entry; question their motives; throw their invitations back in their faces and treat them as low-life cheating scum who don't want to read poetry, play music or discuss science for a few days but plan to dive underground and work, perhaps, as illegal fruit-pickers or waiting staff on poverty wages. Then, to twist the knife, make sure that this routine humiliation of the leaders of tomorrow takes place in just those areas – the Middle East; south and east Asia; Latin America – on which our prosperity in coming years will urgently depend.

Of course, all this already happens – and has, without respite, for years. This column has several times highlighted this suicidal national strategy – recently, when a deal-hungry literary agent from Turkey, guest of honour at the London Book Fair, was refused entry to the UK. Clever, no? Yet we have to bang the same drum once again. The Shubbak festival – London's annual celebration of the modern Arab arts – has been mutilated by visa refusals. One curator of the festival's exhibitions, Yazan Khalili, cannot travel from the West Bank because his application for a visa met with no response. Even more grotesque, Shubbak's literary strand was scheduled to feature a reading by two authors from Gaza, Ali Abukhattab and Samah al Sheikh. Their visas were refused on the fatuous grounds that they were not "genuine business visitors" and would not return home. Thanks to Skype, the conversation did, remotely, go ahead.

Arbitrary, capricious, self-destructive, Britain's visa policy towards short-term visitors of high artistic and intellectual repute is a national disgrace. Of course, no politician dare challenge it because every party is fronted ("led" is hardly the word), spinelessly, by doormats who live in terror of being thought soft on foreigners. I don't blame the media bugbears that so scare them for the pitiable failure of our political class to make the rational, patriotic case for openness. If they had any courage, they would. But they don't, and so they can't.

This latest visa fiasco does point a finger at one interested party in particular. Shubbak takes place with strong support from the Mayor of London's office. Boris Johnson writes that culture has "a key role to play in building understanding with the Arab world". The mayor does get it – as his efforts to simplify the UK visa rigmarole for Chinese tourists shows. However, he remains the grassroots darling of a xenophobic party which will now outbid UKIP in the jingoism stakes. Soon, he has to choose: world-class leader or cheap, populist end-of-the-pier act? Time is running out.

No thanks to our shambolic visa system (another triumph for cack-handed privatisation), Shubbak – until 6 July – does still abound in good things. Thankfully, perhaps, it was programmed before the success of the most famous Gazan in the world right now: Mohammed Assaf, the 23-year-old singer who has just won the Arab Idol TV talent show. On current form, his request for a UK visa would meet rejection on the grounds that the young star secretly yearned to disappear from sight and sweep floors incognito in a branch of KFC.

'Shubbak: a window on contemporary Arab culture': www.shubbak.co.uk

Tales out of court: crossing the lines again

Publishing lore used to maintain that, unlike sports with heavy-reading fans such as cycling and cricket, tennis didn't sell. John McEnroe dented that belief in 2002 with his first memoir Serious; and it was knocked out by Andre Agassi's all-round-the court revelations in Open. Now McEnroe has signed up with Little, Brown for a second confessional, due in September 2014. But will Andy Murray ever wish to update his premature autobiography, Coming of Age? We all know which event would prompt a new edition.

Austen adorns the tenner: in 1808

It is a truth almost nowhere acknowledged that Austen has already appeared on a £10 note. The British Museum has such a note issued by the Alton Bank in Hampshire in 1808. It lists the partners' names: "Austen, Gray and Vincent". The first is Henry Thomas Austen, Jane's brother.

But champions of the novelist who yearn to see Jane adorn the tenner soon – the Bank of England's retiring governor, Mervyn King, has revealed she is "waiting in the wings" for the £10 gig – may care to know that Henry's career as a banker does not augur too well. He flourished for a while and, around 1806, opened an office in London.

But the Alton Bank ceased trading in 1815. Then his London outfit failed. Henry was declared a bankrupt. He became a clergyman: back to the family business that Jane knew so well. She lived long enough to praise his "very superior sermons".