It has not been a happy week for the left. The sharpest blow came on Sunday, no softer for being expected. Ségolène Royal's defeat will extend to 17 unbroken years the right's lock on the French presidency. Remarkable this, when you consider France's place in the progressive imagination as the great European bulwark against both globalisation and America's plans for unipolar world domination. Even in France, which stands up to Ronald McDonald and George Bush, the left cannot win.

Here in Britain the gloomy tidings came earlier. The Conservatives hammered Labour (and the Liberal Democrats) in England, bagging a 40% share of the vote that makes a Tory general election win utterly plausible. Defeats in Wales and Scotland only added to the misery, suggesting that Tony Blair is making his exit just as Labour's 10-year winning streak runs out. Pretty soon there could be right-of-centre leaders in Europe's three great capitals: Angela Merkel in Berlin, Nicolas Sarkozy in Paris and David Cameron in London.

But look more closely. Behind those depressing headlines lurk some encouraging signs, hints that progressives might yet have their day again - some of them from the last place you'd expect.

Start with the home front. Last week's most significant defeat came in Scotland, where Labour had dominated for 50 years. Yet it was not the right who won. It's true the Scottish Nationalists promised a cut in corporation tax, but in almost every other area the SNP attacked Labour from the left - from opposition to the Iraq war and the renewal of Trident to promises to wipe out student debt. And remember, the SNP fought not the government in London but Scottish Labour, which was already to Blair's left. In other words, Scots were choosing between two shades of centre-left and they chose the redder of the two.

In Wales, there was a similar story. Rhodri Morgan's administration was also of deeper red than Blair's in London. And while it lost three seats in the assembly, Plaid Cymru, which sits to Labour's left, gained the same number. Thursday was certainly a bad night for Labour, but that's not quite the same as a pendulum swing to the right.

It's harder, admittedly, to draw that conclusion about France. (Tony Blair's YouTube message of beaming congratulations to Sarkozy is confirmation that the prime minister is leaving office utterly unrepentant, as heedless of Labour party members' feelings now as when he holidayed with Silvio Berlusconi or locked shoulders with George Bush.) Sarko looks every inch the hardman of the right. Yet even he, for all his rage against the 35-hour week, does not buy into the full Blair package. "I want Europe to protect us from globalisation, not let in globalisation as a Trojan horse," Sarkozy declared during the campaign. Rather than let the chill winds of market forces and free trade blow, Sarkozy proposes new barriers to imports from outside the European Union, all in the name of protecting jobs. Not quite one of les Anglo-Saxons, then.

Which brings us to the big surprise. Europeans speak of the Anglo-Saxon or Anglo-American model as a synonym for turbo-charged, take-no-prisoners capitalism. Yet there are some signs, tentative for now but noticeable all the same, that movement is under way even in the US, inside the belly of the capitalist beast. They come partly in reaction to the ever worsening state of inequality in that country. You can pick your stat, ranging from the claim that just two men - Bill Gates and Warren Buffett - have as much money between them as 30% of the entire American people, to the findings by a federal reserve study that the top 10% of Americans now own 70% of the country's wealth, while the top 5% own more than everyone else put together. There was a time when a company boss earned perhaps 10 or 20 times the salary of his lowliest employee. By 2004, that ratio between average chief executive and average worker had leapt to 431 to one, and the gap has got wider. It means that average worker takes more than a year to earn what his boss brings home in less than a day. The result is grand houses on New York's swankiest avenues that were, until recently, multiple apartments but which are now restored to the private homes they were a century ago. Makers of 200ft yachts report record sales. Economists say the last time such a yawning chasm separated rich and poor was in the Great Gatsby years, on the eve of the crash of 1929.

America's politicians have begun to notice. The Democratic presidential candidate John Edwards speaks of the "two Americas". Barack Obama tells audiences that not only is caring for the poor an American tradition, but that "those with money, those with influence, those with control over how resources are allocated in our society, are very protective of their interests, and they can rationalise infinitely the reasons why they should have more money and power than anyone else". Most striking was the Democrats' response to Bush's last state of the union address, given by Senator Jim Webb. He invoked the early years of the last century. "America was then, as now, drifting apart along class lines," he said, deploying the c-word that is now all but barred from British political discourse. Recalling the robber barons who were "unapologetically raking in a huge percentage of the national wealth", Webb gave this charged warning from history: "The dispossessed workers at the bottom were threatening revolt."

This talk connects to the world beyond America in two ways. First, some inside the US are beginning to see a global picture. A new book, Second Chance by Zbigniew Brzezinski, the cold war hawk who served as national security adviser to Jimmy Carter, includes a startling phrase. No leftist, Brzezinski detects what he calls a "global political awakening", a stirring across much of the developing world, among those who are "conscious of social injustice to an unprecedented degree and resentful of its deprivations and lack of personal dignity". Thanks to television and the internet, the global have-nots can now see all that the haves are enjoying at their expense. The hard-headed Brzezinski sniffs revolution in the air.

The second (and related) impact is on the status of the US as a model to the rest of the world. Last weekend a clutch of political scholars gathered in Oxford for a New York Review of Books conference on "The new face of American capitalism". Several suggested that, thanks to a weakening dollar and a narrowing in the performance gap between the US and Europe, the US model was beginning to lose its shine. The debacle in Iraq had also badly damaged American prestige.

This leaves Gordon Brown with a challenge. As one speaker, Simon Head, put it: "The UK has staked much on being the best European emulator of the American model. But if that model is looking jaded, where does that leave us?"

This, then, is the thought Gordon Brown might mull as he watches Blair announce his exit tomorrow. Is it possible that the Blair era of neoliberal certainty is coming to a close, that there are stirrings abroad that call for something else? Might there not be a demand for action, as there was when the last intolerable gap in wealth opened up nearly a century ago - a demand, in short, for a battle against inequality?