David Cameron has invited us to "join the government of Britain". He pledges to put us into "the driving seat, to take the decisions that affect the life of our families and our communities ... We'll give you the power, so you can take control".

But control over what? His idea of the "big society" is pitched at minimising the power of the state, while doing nothing to give people the power to control the private, "free" market and the inequalities it produces.

Without economic democracy, decentralisation of political power will reinforce inequality, shifting power not "from the state to working people" but to those who already have the money, social networks and time to make the system work for them. (See the work of the Equality Trust.)

The present inequality of economic power and its consequences was illustrated on Friday, when 250 former Corus steel workers came together in Middlesbrough to mourn the loss of their plant. Many wore black as they gathered for a last drink together. More than 1,600 workers lost their jobs when the Redcar steelworks was "mothballed" in February. Tommy Dring, who worked on the blast furnace for 33 years, lamented: "I do not think we will see steelworks on Teesside again."

Who made the decision to shut down the plant? Not Tommy. Not any of the workers. Their jobs went because a few top bosses said so – and Cameron's Conservatives have no plans whatsoever to change that.

Cameron says nothing about the power of private corporations – financial and industrial – or the devastating consequences their actions can have for wider society.

He might justify this absence by resorting to the idea that the market itself is the true mechanism of economic democracy. But this tenet of free-market ideology bears no relation to today's economic realities.

The capitalist market today is oligarchic, closed and unaccountable and indeed it is the extent to which it has taken over the upper echelons of the state that is partly to blame for the hollowing out of what political democracy we have had. (See my recent update of Reclaim the State: Experiments in Popular Democracy.)

In Britain today, just 947 people – the directors of the FTSE 100 companies – control firms worth more than £1 trillion. (And those directors paid themselves more than £1bn last year into the bargain.)

So here's an idea: what if we took Cameron's plans for the public sector and extended them to the private corporations that control the economy?

Cameron says: increase inspections of failing schools. Why not strengthen inspections of companies on their health-and-safety record, and whether they are applying the minimum wage? And why not give workers and communities the legal right to trigger these inspections?

Cameron says: give people the right to veto council tax rises. How about people having a right to veto public services – their services, paid for by their money – being outsourced to the high-cost, low-quality private sector? (For a useful source on the damaging sources of outsourcing see Unison's Positively Public campaign.) How about people being able to veto rises in their gas and electricity bills when companies are making massive super-profits?

Cameron says: senior civil servants should have to publish their pay online. Why not private executives? And Cameron's proposal to restrict top public-sector pay to 10 times the lowest paid would be of far more consequence in the private sector, where – to take one example – Tesco chief executive Sir Terry Leahy earns £9.1m, 907 times more than the average Tesco worker.

Cameron says: give public employees the right to form co-ops and take over the department they work for. Why couldn't the government provide support for private-sector workers to form co-ops and take over the factory they work in? After all, surely the way power over the private sector is concentrated in a few hands at the top is utterly incompatible with a democratic society.

Cameron says: encourage local responsibility by directly electing police chiefs. What about encourage economic responsibility by giving workers the right to elect their managers and consumers and workers to have representatives on the boards?

Cameron says: we should "decentralise power". Why not apply this to the City, and experiment with ways of breaking its hold over the British economy? The crisis and bailout have given us a unique moment of power over the banks, when we could turn them into forces for good, working with communities to stimulate green developments.

And who will be in the driving seat when a private developer wants to build a speculative office on land people want for much-needed housing or open space? When Michael Heseltine was in charge of the development of London's Docklands for Margaret Thatcher, using it to expand the City as the centre of international finance, his constant complaint was that local people had too much power and must be bypassed to enable Canary Wharf to be built. He is now Cameron's adviser on urban regeneration. No one believes for a moment that Cameron will support local communities that want to take on the power of commercial developers and their financial backers. (A useful history of the struggle of communities against commercial developers and an example of a community victory is Coin Street, near London Waterloo; for a critical overview of the issues in planning see Planners Network.)

In other words, without economic democracy – and the constitutional reforms needed to enable the people to control executive power – Cameron's invitation to join the government conjures up a toy-town democracy, a patronising attempt to divert our anger from the real centres of power.