A few people in my twitter timeline last night were suggesting that the vote in parliament rejecting military intervention in Syria showed a delayed influence of the march and protests against the launch of the Iraq war ten years ago.

It’s not straightforward to see a direct connection, but clearly the shadow of Iraq fell over parliament – and that included not just what has happened and is happening still in Iraq but also the levels of public opposition expressed to it in this country.

This idea that campaigning delivers sometimes-deferred outcomes reminded me of the anti-roads protest in the nineties – and particularly the quote in Tim Gee’s Counterpower that the protest at Twyford was “an absolutely successful campaign in every respect except stopping the road”.

The road at Twyford was built – and in fact no road was stopped once construction had begun, despite significant displays of opposition. But cumulatively these protests raised the political cost to the government and financial cost to the roadbuilders and led to the planned roadbuilding programme being massively scaled back (until its more recent resurrection).

I also thought of the suggestion (in A Radical History of Britain) that Shelley’s response to the Peterloo massacre – the poem ‘The Mask of Anarchy’ – inspired Gandhi and was chanted at Tiananmen Square.

Rise like Lions after slumber

In unvanquishable number,

Shake your chains to earth like dew

Which in sleep had fallen on you –

Ye are many – they are few.

The women and men who attended the protest – and bore vicious attack for it – were acting with a sense of solidarity and justice whose ripples were felt far and wide.

Nobody planning the protest St Peter’s Field in Manchester in 1819 wrote out a theory of change setting out this chain of results. But campaigning is sometimes about sowing seeds even if you don’t know when or where (or even if) they will germinate.