Tony Blair's handling of the fire dispute has encouraged confidence among ministers. Yet wiser heads in the cabinet may remember that the history of the British left includes times when small disputes have triggered major shifts of support. One hundred and twenty years ago, every trade union of any size gave financial and political backing to the Liberal Party, before finding that this party was more interested in the values of a small number of go-getting employers than they were in the unions.

One Richard Branson of the nineteenth century, Samuel Lister in Bradford, believed that by keeping tariffs on imported goods to a minimum, the entire nation could be kept in a permanent condition of prosperity. Wealth would then inevitably flow downwards from rich to power. Partnership could reconcile the interests of workers and employers - in the speeches of political and business leaders - until the workers went on strike.

Britain's first labour party, the Independent Labour Party was established in Bradford in 1893 following an especially harsh dispute at Lister's Mill.

Then in 1901, the judges changed the law to increase trade union legal liability, the infamous Taff Vale ruling. The unions expected the Liberal Party to reverse the decision. In the absence of Liberal support, they were forced to turn left instead, establishing a Labour Representation Committee - today's parliamentary Labour Party.

Then, as now, the unions were divided between leaders familiar with the old rules of patronage, and a younger guard. The leaders of the move away from the Liberals towards Labour were the rail unions (the ancestors of Mick Rix and Bob Crow), and the dock labourer's union (now incorporated into the TGWU). The fire-fighters played little part. Like other public sector professions, their industry was organised late.

Taff Vale enabled businesses to sue unions for profits lost during strikes. It was seen as a legal attack on the right to strike. It was as harsh in its time as today's much-trailed proposal to make strikes unlawful in key sectors of the public services.

History never repeats itself precisely. Taff Vale came from the law lords, nor Parliament. It arrived at the end of a series of union defeats, while today's strike is at an upward curve of the movement. We cannot know how fire-fighters would respond to defeat.

But is it so odd to draw these parallels? Tony Blair may remember that the FBU was the first union to vote to democratise its political fund, its conference voting to allow support for non-Labour candidates, where they endorsed the union's programme. This decision was taken in 2001, and was partially-reversed at the conference this year. Delegates pulled back, after an impassioned plea from their leaders. Then was not the time. Yet the FBU remains at the front of a group of unions, all considering the value of donating to Labour in the future, and this at a time when Labour's coffers are at their emptiest.

Such options as the government's power to change the law - or its ability to use police and troops to take control of the fire engines - carry risks greater than the peaceful settling of the dispute. In the battle with the FBU, the momentum is now with Blair. If he plays his hand too strongly, though, then victory could yet prove more dangerous than failure.