Bear in mind, when I say this, that I was - and still am - pretty sceptical about the whole idea of bombing, and especially when civilians will undoubtedly get caught in the crossfire and when there appears to be little in the way of a plan to achieve our objectives.
I say that as a way of putting in context the sense of despair I had listening to the demonstrators. All they could think of chanting was "Don't bomb Syria, Don't bomb Syria".
The whole symbolism of demonstrations is so rooted in 1917, with its banners and slogans and clenched fists and rhythmic chanting, that it seems part of another age. It certainly seems meaningless. And vacuous. And completely pointless, if not counter-productive (especially given that other anti-war campaigners seem devoted to death threats and their own kind of violence).
I mention all this because of Larry Elliott's column in the Guardian, which shows just how much the UK economy is going back to the disastrous patterns which led o the 2008 crash - record property debt and a looming housing crash, which will once again bring down the banks.
This is tragic because it demonstrates just how little the coalition's objective of re-balancing the economy has been allowed to wither - despite Vince Cable's achievements in rebuilding UK manufacturing.
I'm not a conventional economist - economists would say I wasn't one at all, and perhaps they are right. But I can begin to see what seems likely to happen. A re-run of the banking crisis of seven years ago, followed this time by a major shift of economic direction.
But to make that shift, we will have to find some way of bringing that new approach into the mainstream, and neither the chanting left nor the dull and conventional right - even more wedded to gesture policies than the rest of us - seem likely to do that.
It is an urgent and obvious task for the Lib Dems. But will they wean them off gesture policies in time?
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