The argument that Scottish independence will lead to a new Dark Ages depends on four propositions:
1. Scottish independence means that Britain's nuclear deterrent will need to be relocated to Devonport.
The UK's current nuclear weapon capabilities depend on four Vanguard-class submarines based at Faslane in Argyll and Bute, and on the ballistic missiles and nuclear warheads stored nearby at Coulport.
Local political opposition to locating the nuclear deterrent in Wales or Northern Ireland means that a base will have to be found in England.
Devonport, in Plymouth, is the largest naval base in Western Europe and is the sole nuclear repair and refuelling facility for the Royal Navy. Even then, extensive work will need to be carried out to make Devonport suitable as a base for the submarines.
2. Devon achieving nuclear capability will lead inexorably to Cornwall developing its own independent nuclear deterrent.
It is inconceivable that Cornwall would sit idly by, while Devon flexed its nuclear muscles, itching to blow Truro to kingdom come. That Cornwall is oppressed by English rule is bad enough, but for Devon to possess weapons of mass destruction would be seen in Cornwall as a deadly threat to the peace and stability of the region, if not the world.
A devastating nuclear attack by Devon on Brittany, Cornwall's strategic celtic ally, could be over within less than 40 seconds.
The realm that produced notables such as Captain William Bligh, Sir Arthur Quiller-Couch, Rick Stein and Rory McGrath would not hesitate to summon up its brightest and best to create the weaponry necessary to deter the Devonshire aggressors.
3. Then all hell breaks loose.
If the Cornish get nuclear weapons, we're all done for. That Pasty Tax is out, for a start. Bitter rivalries over the order of jam and cream on scones will then turn into an all-out South West civil war. Meanwhile, aggressive exports of clotted cream and Cornish fudge will quickly clog the arteries and rot the teeth of the decadent English middle classes.
With Cornish military power in the ascendant, radioactive piskies will multiply and infest the whole mainland. Roaming bands of tin miners will terrorise the land, so stern and taciturn they reduce the gruffest Yorkshiremen and hardest Geordies to girlish simpering. Wreckers, pirates and zombie-like surf dudes will cause devastation along the coasts of the British Isles. Jamaica Inn morality will rule.
4. The Greater Cornish Empire rises.
A resurgent Mebyon Kernow seizes power, claiming that only they can return order. They are sustained by vicious elderly watercolour artists brandishing brushes and a distracted air, and wearing black shirts (well, black with a white cross in the middle, and more like smocks than shirts really).
They are led by a newly awoken man called Arthur Pendragon, who promises to unite the celtic diaspora and drive the perfidious Saxons into the sea. He ruthlessly deploys massed ranks of harpists, bagpipers, and richly timbred choirs to great military success across the British Isles.
From then on, it's a few simple steps to the abolition of paper in favour of celtic stone; the replacement of the internet and telephones with signal fires; the reworking of medicine and dentistry in line with an all-encompassing philosophy of "It's just a scratch. Just leave it."; the rejection of roads as "Roman rubbish"; the eradication of weird foreign foods such as potatoes, tomatoes and rice; and feudalism.
So be careful what you wish for, Scots. You cry, Gibson-like, for freedom now. But you may end up annexed by a Greater Cornish Empire. "Onen hag oll" (One and All) will ring out from Land's End to John o' Groats.
Think carefully before you vote "Yes" to Scottish independence.