I've just noticed OurKingdom's strapline: 'investigating the crisis of democracy in Britain'. Yes. It's a crisis - and we have to ask questions.

On Friday I went to a preview of We are Many, a film by Amir Amirani about 15 February 2003, when maybe 10 million people marched against war in Iraq. It was the world's first global citizen protest.

The story of the film is intriguing: joining a march on impulse, as a first-time anti-war demonstrator, Amirani was seized by the power of the event. Two years later he decided to make a film. Eight years on he has finished it, but along the way it has grown and changed. Through chance encounters he learned how 15 February resonated through Tunisia's and Egypt's uprisings. Then came the August 2013 votes against war in Syria at Westminster and the US Senate: another twist in the tale. So it turned from a film about an event into a film about a process; no longer about hope dashed but about a long-term hope.

Necessarily, Amirani simplified the story. What, as one of Friday's audience asked him, about earlier actions? 15 February was not a creation out of nothing. It too stood on the shoulders of what went before: the Aldermaston Marches, CND; the Suffragettes and Chartists; the Quakers in whose building the Stop the War Coalition first met. More broadly: where does the 2011 Libyan intervention fit in? And again, remember the children who came out of school to protest, whose politicisation helped sow the seeds of Occupy.

The film throws up more questions than it can answer. That's a sign of its power - for it is deeply powerful. Go and see it when it's released next year. Take your friends.

It is a story of horror, and of life-giving creativity. Shock and Awe and its aftermath were terrible. Interviews—notably with a senior member of Bush's team and a US veteran—unfold the long-running deception in which Blair participated. Music and humour are beautifully, subtly used to toss us from anguish to anger to heart-swelling joy at activists' unceasing energy. We see the global reach of the movement: footage of marchers from Australia across Malaysia and up through the Indian subcontinent, across Russia and Europe, down through Africa to—hilariously—Antarctica; up through the Americas. The infectious vim of an Italian activist sweeps us up; the courage of American women still confronting their war criminals commands respect (and laughter).

Tony Benn calls in the film on our anger and hope, basic tools for those who want to build a better world. Amirani sets out to kindle both and succeeds, superbly.

But however unambiguous the anger, it's an ambiguous hope. What now of the Arab Spring? And despite that Syrian vote, we're bombing Iraq for real and Syria by proxy. The story goes on.

Even at its most hopeful, the film says that marching is not enough. Many of the marchers interviewed could not imagine that Blair could persist in face of such a protest; others say they never thought they'd win, but had to act. Will Saunders and David Burgess, who painted NO WAR on the Sydney Opera House sails the day war started, did so because they could do no other.

We are Many shows Blair at the Labour Party spring conference in Glasgow, likening the marchers to an over-grown focus group which cannot dictate policy. That got a gallows-laugh. It's a constitutional point - which reveals Blair's constitutional stance. He implied that marchers and focus groups could not shift him, the executive: that he held power. No. Decision-making power lies, in theory, with our parliamentary representatives, not with the executive. If marchers and focus groups could shift their representatives, then they could rightly dictate policy.

In theory. The problem, as the marchers knew and the film portrays, is that power lies not with the Commons but behind the scenes. With the executive and the financial interests which support and use it. With the little circle round Bush, whose lead Blair made us follow. That's the crisis of democracy.

We know—the electorate know—that we are routinely lied to; that government's picture of its goals is a simulacrum of the truth; that the interests served are not those of the mass of people; that the protections and freedoms of law and public services are increasingly a hollow shell. This would be empty rhetoric if it were not scrupulously evidenced. But the evidence is all around. We only have to look, read, listen. We talk peace and market weapons around the world; we last sold military goods to Syria in June 2014. We talk of ending child poverty and knowingly ensure it worsen. The party of the rule of law denies effective law to those who once claimed Legal Aid. A 'veil of secrecy' drapes an unaccountable 'shadow state'.

So - how to respond?

I saw another film recently, showing the flip side. We Are Many says 'never give up'. Conspiracy shows what happens if we do.

It's the story of the 2-hour Wannsee Conference of 1942 that rubber-stamped the Final Solution. Mesmeric Heydrich leads it, humourless Eichmann by his side. One by one the 13 invitees show us the paths to complicity. Passionate Jew-despising ideologues; committed believers in the rule of law; idealistic lovers of tranquil beauty; brutal enjoyers of power over despised others; harassed bureaucrats staving off melt-down; militarists wedded to total obedience. And men in despair who know that nothing can stop this march to moral chaos; who, powerless, give up resisting.

Out of this web it has a single message, that of Arendt's Banality of Evil. Evil comes when we stop thinking. "...[T]he only specific characteristic one could detect in [Eichmann's] past as well as in his behavior during the trial... was something entirely negative: it was not stupidity but a curious, quite authentic inability to think." That's what the followers at Wannsee did: they opted to stop thinking. Some eagerly; some unconsciously; some in anguish, for to continue thinking would be unbearable.

This is the final, terrifying, refusal of responsibility. We are Many shouts loudly in reply: never give up! Keep democracy alive. The notion that we're together, energising one another is vital, for this is hard. Not one day's march but constant willingness to think, listen, read, watch, respond, speak, act. What is happening to the balance of rich and poor, of powerful and powerless, of free and unfree, within the UK and beyond? How is the rule of law being eroded, in so many ways? Perennial issues of proportional representation, the power of the Whips, the growing number of the ministerial career-opportunities that sap backbencher independence; complex questions about financial global interests. The questions are endless.

But the price of freedom is eternal vigilance. Never stop asking. Never accept without reflection. 'Eichmann has brought up the radical danger of "such remoteness from reality and such thoughtlessness."' Is this over-emotional? Exaggerated? By definition so, if sober rationality be defined by pragmatic acceptance of what is, padded against the lived experience of suffering. In those terms, to be alive is to exaggerate.

So never give up. Keep thinking. Hang on to anger and to hope.

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