The mood among Labour MPs has turned black since the start of the year. Pre-Christmas optimism that Gordon Brown's strong leadership in the economic crisis would allow him to defy the normal rules of political gravity has given way to fatalism about the probability of a big election defeat. As with the media, the politicians swing wildly, like a pendulum that rarely rests in the middle.
Amid the gloom, Downing Street sees a ray of hope. Polling on the nation's mood, presented to Labour by its advertising agency Saatchi & Saatchi, shows that, even though people are deeply pessimistic about their short-term prospects, they remain surprisingly upbeat about the country's longer-term future. "Britain will get through this," is a common view.
The wildcat strikes over "foreign workers" alarmed the cabinet. Yet there is little sign of what James Callaghan called the "sea change in politics" that would sweep him out of office in 1979, or that the public thinks that a new "British disease" makes this country the "sick man of Europe" - slogans that Margaret Thatcher used to justify her harsh medicine.
Today, many people believe Britain has a good future, are proud of their country and, in many cases, of their communities. Many warm to a touch of nostalgia about better times past. Brown's calls for the country to pull together in a kind of Blitz spirit plays to this feeling. So, perhaps, did his decision to set up a "war cabinet".
Ministers concede that with the speed and scale of the crisis, they have not got everything right. But Saatchi & Saatchi's presentation has convinced them that David Cameron is getting something wrong. They think the Tories' strident criticism of the government's anti-recession measures sends a subliminal message to voters that they want them to fail, and will be seen as unpatriotic.
This is more than wishful thinking by ministers clutching at any straw. At the recent World Economic Forum in Davos, Switzerland, there was disquiet among business leaders that Her Majesty's Loyal Opposition could make the crisis worse by running Britain down. Some expressed doubts about the Tory attacks on the fall in sterling's value with phrases such as "bankrupt Britain" and with Cameron's recent warning that the country might soon rush back into the arms of the International Monetary Fund - a deliberate echo of Labour's past failures, this time from 1976.
While Cameron and George Osborne, the shadow chancellor, go for the jugular, the more experienced Kenneth Clarke distances himself from their approach. In his first television interview since his recall to the Tory front bench, Clarke told the BBC's Andrew Marr that Britain going bankrupt or going begging to the IMF was not a "realistic possibility". He added pointedly: "I think it's very important to realise the constraints of a responsible opposition."
Saatchi & Saatchi's findings convinced Brown that the Tories have overstepped the mark and partly explain his decision to accuse Cameron, at Prime Minister's Questions on 4 February, of running Britain down: "He [Cameron] goes around the world talking the pound down . . . saying that we are going to have to go to the IMF; he goes to Switzerland and says that the British economy is weak. He has decided that it is in the interests of the Conservative Party to talk Britain down, and he should be ashamed of himself."
While Labour was in opposition, Tony Blair was careful to avoid the charge of being negative about Britain, especially when he was abroad, in line with a long-standing convention. "It was an iron rule for us. The Tories are getting it wrong. They are undermining Britain and it will rebound on them," says a former Blair aide. A YouGov survey for Channel 4 this month found that 53 per cent of people agree that Cameron is "talking the economy down for political purposes and risks making things worse by damaging confidence", while 30 per cent disagree.
Might the Conservatives be going excessively negative in other areas, too? Privately, Brown aides admit to a grudging admiration for the opposition's "broken society" slogan. "It's a blank page, allowing people to project on to it whatever their biggest concern is - crime, antisocial behaviour, housing, and so on. It's a rich seam for the Tories," says one Downing Street adviser.
Yet most people don't appear to think that society as a whole is "broken", and so the line also has dangers for Cameron. The Tories risk looking opportunistic if all the public hears is their claims that Britain is broken and doesn't get a message about how they would fix it.
The party denies the charge. It regards Brown's calls for unity during the crisis as an attempt to stifle any criticism and prevent the opposition playing its proper role in a democracy. The Tories insist the bipartisan approach they announced last autumn was always going to be limited to the immediate banking crisis. They are adamant that they are not running the country down, that there is no convention that prevents discussion of the level of sterling and that they do not want the government's anti-recession measures to fail. It is true that Cameron's warnings about Brown's irresponsible "borrowing binge" are not a piece of positioning; he really believes it.
"It is a difficult balancing act," one Tory frontbencher says. "We are not being negative about the country. But when the government's measures are not working, we have a duty to say so. It's the oldest trick in the book to accuse your opponents of being unpatriotic."
Cameron has changed his strategy and language since the autumn. The Tories built their platform for government in prosperous economic times and realised it needed major reconstruction. Suddenly, fixing the broken economy would have to take priority over the broken society. The Tory leader who once said "Let sunshine win the day" and that GWB (general well-being) mattered as well as GDP (gross domestic product) adopted a sombre tone, desperate to head off Brown's wounding charge that he is a "novice". Cameron made a flurry of speeches on the economy. Osborne, too, attempted to be more serious as he tried to escape his image as a plotter and political point-scorer. Clarke's recall showed that the Tories needed more experience and gravitas.
However, Labour's focus groups found that women do not like the harsher Tory tone; they prefer the Cuddly Cameron version. "He is not the guy we thought he was," is a typical comment. But his tougher line plays better among men.
Perhaps surprisingly, YouGov found that voters divided evenly when asked whether a Cameron government would do far more to help the victims of the recession than the Thatcher government did in the Eighties. Some 42 per cent agree while 43 per cent disagree - perhaps a sign that Brown's gibe that the Tories would "do nothing" has hit home and that they have not finally laid their "nasty party" image to rest. Similarly, only 20 per cent of people regard Cameron as a heavyweight, but 57 per cent view him as a lightweight.
Although the Tories have now re-established a double- figure lead in the polls, the small print suggests that Cameron has not restored his personal ratings to last year's levels. Labour strategists hope that the party's dip in the polls reflects an anti-government protest as the recession bites, rather than positive support for the Tories.
Last month's sleaze revelations in the Sunday Times concerning four Labour peers, which will result in long-overdue changes to the way the House of Lords is regulated, provide another parallel with John Major's long, inevitable goodbye. Yet, despite Brown's mounting problems, the Tories have not found the perfect storm they desire: widespread public acceptance that there is a broken economy and broken society, turning into an unstoppable "time for change" tide.
Andrew Grice is political editor of the Independent