Much of what this year will bring politically is unknowable – the scandals we haven't heard of yet, the deadly, devil details of economic hard times. But here's my main prediction: 2012 will see the return of something British politics had almost forgotten about – old-fashioned left-right politics.

After the "third way" and triangulation of the Blair project, created to erase Labour's leftwing identity, and David Cameron's cuddly-fication of the Conservatives in response, we have had the blurring effect of Liberal Democrat cover for the Tories in the coalition. It's as if, over the past 15 years, someone had drawn a huge wet sponge over the party system, leaving only a swirling, chalky mess. This was the centrist politics of good times, when the main parties by and large offered us electoral bribes in a genteel consumerist competition.

Yes, Labour had a stronger social conscience, and yes, the Tories were keener on cutting taxes than the Blairites, but too much of it was nuance and delicate pastel shades of difference. It led to cynicism, and is partly responsible for the widespread anger and disillusionment with the political system. But now it is surely coming to an end, for big, obvious reasons and smaller, less obvious ones.

The big reasons start with the economy. There is no happy-days-ahead prospectus. Incomes will fall, unemployment will rise, the cuts will fall heavily on decent people doing important jobs, and the path to prosperity and a better balanced economy will be long, hard and slow. I don't believe this can be altered by a slight twist of the fiscal tap and nor does anyone else. The real question is different: in hard times, do we hang together as a society or do we break apart, as the super-rich float off and millions sink into deep poverty?

By giving a knighthood to a Tory donor and hedge fund manager who made millions out of the collapse of Northern Rock, Cameron simply shows himself out of touch, behind the mood of the times – as his vigorous critic the archbishop of Canterbury is not, bravely warning about the social consequences of Tory policies. Even Cameron must have been surprised by the reaction to his New Year's honours list. It's a red-light warning story. It's similar to Cameron's mishandling of the Murdoch, Coulson and phone-hacking tale.

People are sick to the stomach of cosy little networks of the super-rich and client Tory ministers getting together to agree special measures for the City, or cuts in higher rate taxes. And to quote something that Cameron likes to throw across the dispatch box at Ed Miliband, the prime minister just doesn't get it.

The second big reason for the return of left-right politics is related to that, because it's Europe. What provoked the Cameron veto, so hugely popular in the Tory party? The special interests of the City. I've argued before that Labour must not defend the EU when it imposes austerity budgets on nations without any democratic safety mechanism. But what seems to be happening here is that the drive to get Britain out of the EU is coming from the same Atlantic freebooting financial clique that caused the banking crisis, led by the same super-rich now so suspected throughout Britain.

For all their faults and mistakes, we have a continental EU leadership that still believes in social solidarity and sharing the pain, versus a British government arguing for the primacy of finance capitalism. The Conservatives have made their choice. The Tory benches are hugely Eurosceptic and their most popular ministers, such as Iain Duncan Smith, are in the vanguard. According to a ConservativeHome poll for the Independent, 54% of Tory members say their ideal vision is for the UK to leave the EU and sign up for a free trade agreement. Cameron's veto was his acknowledgement of this reality.

In the year ahead, this growing pressure will be very hard to resist, as Duncan Smith has already made it clear he's not prepared to compromise on this. Cameron must privately hope that Boris Johnson loses the 2012 London mayoral fight to Ken Livingstone, because Johnson has become the populist leader of the anti-EU cause. He is already a thorn in Cameron's side, and will be all the more so if he wins resoundingly in May.

This is far more dangerous for the Tories than it seems, and a huge opportunity for Labour. Despite the euro crisis, and the profound problems the EU faces, the idea of jumping overboard in the middle of a vicious recession may not appeal to most British people.

Oddly, perhaps, the people making that argument most eloquently are the Lib Dems, which leads me to the more minor reasons for the return of left-right politics. Up to now (despite tantrums, policy rows and last-minute compromises) the Lib Dems have given Cameron's Conservatism a useful mask. Benefits cuts, the veto, kow-towing to media tycoons and the City … yet thanks to the Lib Dems, the right has not seemed as right as it really is.

The mask is not so much slipping, as taking itself off. Vince Cable, the business secretary, seems close to breaking point – and he is not the only one. Having failed over voting reform, the Lib Dems see Europe as the one thing they cannot compromise over any further. Chris Huhne, the energy secretary, spent 2011 being roasted for the driving points controversy, but if he breaks free he will be another vocal critic and a hate figure for Conservatives. I don't expect the coalition to fall this year, though we should rule nothing out. But it is going to be a much less convincing alliance. As the anti-EU Tories charge ahead, the right will be more nakedly itself.

Which takes us, finally, to Labour. This should be Miliband's moment. Struggling out of the wreckage of the Brown government – which history will be kinder to – and the horrible mistakes of Blairite foreign policy has been difficult. But if Labour positions itself properly, defending fairness and social solidarity, speaking up for the European cause and taking on the super-rich then it has the chance of again catching the national mood. Getting the tone, language and policy choices right matters infinitely more than the trivia of individual character tics.

Left-right politics is about the majority versus the powerful minority. The majority have rarely been angrier or more worried; the minority rarely less powerful. It is a potent brew, which will make for a fascinating year.