An existential threat? Why did Cameron not warn us before?
Or did he only just come up with the idea in order to cover his tracks over Libya?
DAVID CAMERON in his self-serving foreign and military policy increasingly resembles Colonel Cathcart - Yossarian's commanding officer on the fictitious Italian island of Pianosa in Joseph Heller's novel, Catch 22.
Cathcart is most famous for repeatedly raising the number of missions the men have to fly to complete a tour of duty. This becomes the bane of Yossarian's life, as every time he comes close to obtaining the target number of missions for being sent home, Col Cathcart raises the tariff again. The British Army, I suspect, is beginning to understand the feeling.
Just as they are finally disengaging from Afghanistan, Cameron has found a new existential enemy in the Sahara desert: in the unlikely form of a group of 'Mad Max Militias' - some Islamist, some merely opportunist tribal bandits.
One group, controlled by a long-time troublemaker from Mali, Mokhtar Belmokhtar, was responsible for the attack on the Amenas gas complex in eastern Algeria. Other groups have been responsible for the destabilisation of Mali prompting the French military intervention on 15 January.
Col Cathcart has a further characteristic that drives forward Catch 22's plot and provides some of its blackest comedy - his devious mastery of disguising his cock-ups with misleading language. Cameron's recent high-octane activity on Algeria beautifully demonstrates that the spirit of Cathcart is alive and well in Downing Street.
Few serious commentators view any of the groups as an "existential threat" as Cameron described them.
It is true they have grown stronger of late - mainly as a result of the fall of Libya's Colonel Gaddafi, who offered gainful employment to many of the wilder tribesmen in his own security forces, and was an implacable enemy to any group with jihadist sympathies. In any case, parts of the Sahara have always been lawless and violent "ungoverned space" – read Beau Geste: nothing the French Foreign Legion can't keep the lid on as they used to for more than a century.
But by rebranding rag-tag Islamist and Tuareg gangs Cameron is able conveniently to cover his tracks over Libya where he was warned time and again that overthrowing Gaddafi would have some unpleasant consequences. He is able to sex up a consequence of his own poor judgment into a great and implacable force of history.
Indeed, there are reports that a split emerged yesterday in the alliance of Islamist militant groups that seized control of northern Mali last year. A negotiator from the Ansar Dine group (defenders of the faith) has said he is now part of a faction that wants talks with the government and has distanced the group from al-Qaeda's North African umbrella organisation, AQIM. This is more reminiscent of the squabbling terrorist groups in Monty Python's The Life of Brian than an "existential threat".
Even if Cameron is sincere in his belief about the threat, it seems odd that he hasn't warned the country before; and even odder that he is going ahead with major cuts to the armed forces, particularly the Army (likely to be the most important force in a desert) which announced a further 5,300 redundancies on Tuesday. How can the blueprint for the future armed forces dreamt up nearly three years ago still be the right one in the face of this new existential threat?
The prime minister is, of course, absolutely right to offer logistic support to our French allies if for no other reason that they actually have an aircraft carrier and we don't. That some of the UK's giant C5 Galaxy aircraft supporting the French may be flying out of RAF Gibraltar, no doubt to the irritation of the hyper-sensitive Spanish Foreign Ministry, merely adds icing to the cake.
The best approach we can make to maintain our national security is much simpler and less dramatic than babbling about 'existential threats' far away. It involves plain commonsense and sustained effort in three rather obvious areas in which the coalition government has a dismal record - securing our borders, balancing our books and maintaining strong armed forces.