The Euphrates is flowing through David Cameron's drawing room

By Paul Goodman
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The image is borrowed from Clarissa Eden, wife of Anthony Eden, who told a group of Conservative women in the aftermath of the Suez crisis that "in the past few weeks I have really felt as if the Suez Canal was flowing through my drawing room".  At first glance, there is no reason why the Syrian tragedy should provoke a similar image.  We have no immediate interest in Syria.  Our armed forces have withdrawn from Iraq.  They are now being scaled back.  The conflict in Syria is being transformed from one of protest versus tyranny to one of Sunnis versus Alawites (with the Christians and other religious minorities nervously sheltering behind the latter).

It is thus part of the wider struggle between Sunni and Shi'ite Islam in the middle east (see above). Saudi Arabia is leading for the Sunni world, or rather for its own form of Sunni Islam, the takfiri version which goes all the way back to the Kharijites, and is expressed in the oil-financed export of its extremist modern successor, Wahaabism/Salafism.  Iran is leading for the Shi'ite one, or rather for its own form of Shi'ite Islam, shaped by the Khomeini revolution.  The latter threatens Israel, an ally; has had a calamitous effect on the balance of Lebanon, and occasionally strikes at Jewish targets outside the middle east.

But although it is a threat to the stability of the region, it hasn't been one to the security of Britain, at least to date.  The maniacs who murdered a soldier on the streets of Woolwich, and who executed the 7/7 atrocity, were all inspired by the takfiri tradition, of which Al Qaeda is a part.  So in so far as we have any national interest in Syria at all, it is in keeping that movement of ideas and people out of power there.  To do so we would, were we to intervene, have to do much more than add to that $3 billion of small arms that has already gone in.  We would have to supply rebels with anti-tank and anti-aircraft missiles.

This would mean training them to use these weapons, which our military would need to do.  The latter would therefore be required to identify which rebels are democrats and which are extremists, a task for which they are not equipped and terms which may make less sense in atrocity-torn Syria than think-tank seminars in London.  If the rebels won, Britain's shrinking armed forces would then be required to police a country divided by religion and ravaged by war.  Even abroad, the Syrian opposition is increasingly Islamist in flavour - refusing recently to work with Mohammed Al-Yacoubi, a leading Syrian cleric, Sufi and opponent of the regime.

The Times (£) reports this morning that the American Government is now prepared to send small arms to Syria.  The apparent reason is the use of chemical weapons by the Syrian Government, but that these have been deployed has been known for some time. The real reason is doubtless that the Obama administration is spooked by the prospect of Assad winning the war.  His forces have taken Qusair.  They are poised to take Aleppo.  Britain and France have been pushing to arm the rebels. The question now is whether the Cabinet and Parliament will and should agree to Britain doing so.

Some reports of Cabinet discussions could be read as suggesting that George Osborne and Michael Gove are in one corner, clamouring for war in Syria, with Ken Clarke and Sayeeda Warsi in the other, urging that nothing be done.  Having made enquiries, I'm certain that this picture is very wide of the mark: one Cabinet Minister described discussions as "agonised", and stressed that no easy options are available.  That may be so, but choices certainly are.  There must be no British troops on the ground in Syria nor planes in the air there. And as Julian Lewis wrote on this site, Parliament must vote before any arms are sent.