Looking at British politics through the prism of the Labour conference, the unwary may mistake the party's passionate hope of a quick return to government for the reality. But Labour left Manchester more confident about its chances in 2015 than it has cause to be.

Seen through the eyes of Ed Miliband's optimistic new generation, the political wind is rising before the anti-coalition storm breaks out in earnest after the spending review is announced on 20 October. The Conservative-Lib Dem novelty is wearing off. The deficit-reduction strategy could be blowing toward an Irish-style abyss. The Lib Dems are haemorrhaging support. And George Osborne is about to put the public services to the sword with a brutality that will play into Labour's waiting hands.

That's the argument. Granted, something like this is not impossible. But in general the left is getting ahead of itself. To understand why, Labour might put themselves in their opponents' shoes for a moment this weekend. Because, from the point of view of the Conservatives, who gather for their conference in Birmingham on Sunday, what's not to enjoy about the political scene right now?

Back in power after 13 years, albeit only in coalition, the Conservatives command more of the political stage than their rivals. Labour, ahead in some post-conference polls but behind in others, have just elected a leader whom ministers dismiss as promising merely a better yesterday. The Lib Dems, with no alternative but to stay loyal to the coalition, are taking a lot of the anti-coalition hits. David Cameron, managing to float above the fray, is a popular prime minister. The public recognises the deficit must be tackled.

In fact, as Conservative ministers will tell you, things are even better than that – for three large, serious reasons. The first is that the coalition is not merely popular and seen as having the best solutions – least worst if you prefer – to the deficit, it also actually works. In the technical sense, it is a good, deliberative government. Cameron and Clegg trust one another. Though the angry Liam Fox may be an exception, ministers are stickers rather than quitters. The coalition agreement is still holy writ. The government has a five-year programme and a working majority of 83. This is still a stable government playing a long game.

The second reason is the deficit strategy. To some on the left the claim that the government's prospective cuts may be a source of political strength is barely credible. It is an article of Labour faith that the country will revolt against the cuts and sink the coalition. For the moment, though, this message is based more on hope than fact. More of the public still accepts the coalition's case for action than Labour's case for caution, and by a useful margin. That mood could be more resilient than critics imagine. Ministers hope that once the reality sinks in that cuts of 20% or 25% in departmental budgets will be spread over four years at around 6% per annum – not yet sufficiently understood, they tell themselves – the pain will not seem as devastating.

Both coalition parties are braced for damage. This is the lowest time, say Lib Dems. The worst, Tories agree. The politics of the autumn, with the spending review, the defence review, John Hutton reporting on pensions and John Browne on universities, make this an intense period. Lib Dems know there could be defections and admit Labour has been winning the argument that the cuts are too fast and deep. The May elections will be "bloody difficult", say the Tories. The referendum on the alternative vote may suffer collateral damage. But the IMF's approval for the coalition budget this week is a big endorsement, ministers say. And growth is still holding up.

The cuts are difficult but doable, insiders insist. The stumbling blocks are in defence, higher education, parts of the welfare budget and some early years programmes. The police budget remains unresolved too. But the key spending ministers now speak with one voice against the holdouts. Will the public revolt over the slashing of navy aircraft carriers or even, now that the graduate tax option is fading, over a big hike in tuition fees? Tory strategists think not. Look at this week's European protests, ministers say – passionate protests but not pivotal. The same may happen here.

The overriding task right now is to see the country through to better times, ministers argue. Do that, and the way opens up to a Tory victory in 2015, or at the least the re-election of a coalition that will have proved it works. That's where the coalition's third big call kicks in after 2011: long-term radical reform of the public services, localism and greenery. Smarter minds in Labour get this. What will be the Labour message, a delegate asked Alistair Darling this week, if by 2014-15 the coalition can say the tough medicine has done its job and better times are in view? It was a very good question – and Miliband will need a very good answer if that moment comes.

Parts of Labour – and a few excitable libertarians in the coalition – have talked themselves into believing that Osborne will reduce the entire welfare state to rubble as an act of counter-revolutionary small-state zeal. Nonsense, say Tory colleagues. This is not a government like Margaret Thatcher's, squeezing the state for ideological reasons, says one senior minister. If the aim was a small state, the NHS would not be protected. When Clegg says that public spending will emerge at around 41% of GDP, top Tories agree that the figure is realistic. The spending review is not a smokescreen for a US-style small-state drive, they insist. If that 41% figure holds up, Tory claims of a serious centre-right realignment in British politics would be worth taking seriously.

A year ago, in his 2009 conference speech, Cameron made a pre-election lurch to the right, saying the economy had been wrecked because government had got too big and done too much. A few weeks later he hastily corrected that course. Which is the true Cameron? The mood music this week says there will be no repetition of that error in Birmingham.

It is tempting to say that the Tories had better enjoy themselves now because the good times for the coalition are about to give way to the long night of unpopularity. But is it true? The evidence is not just mixed but in many ways unconvincing. As long as the coalition is more trusted than Labour on the economy, Cameron more trusted than Miliband as prime minister, and the government's approval ratings are positive – all of which are currently the case – the Tories will have good reasons to stay confident for far longer than their opponents would like to admit.