Andy McSmith: Without public support, unions lack the power to defeat the Government

This is not 1926, nor 1974, nor 1979, nor the year of the great miners' strike. There may be more and bigger strikes to follow yesterday's, but the present conflict between government and unions is only a shadow of the great industrial confrontations of the past.

In the past, when a big industrial union such as the National Union of Mineworkers called members out on strike, tremors went through the whole economy. In 1972, the miners forced the country on to a three-day week. Two years later, they brought down the government.

Even if the public sector unions succeed in bringing a million or more people out on to the streets as the present dispute escalates, the impact on GDP is not going to be great, and the Government is not going to be forced to call an election to ask the voters "Who rules Britain?" as Ted Heath had to, 37 years ago.

Changing patterns of production and the employment laws passed in the 1980s have shrunk the unions and reduced their power. The law no longer allows them to impose closed shops, organise mass pickets, or call strikes without a vote. The unions that make up the TUC have half the membership they had in 1979 – just over six million. The members lost were, typically, male manual workers in heavy industry.

Now the unions' strength is in the public sector. Take out members who work for the NHS, civil service, local government and in teaching, and most of the TUC would disappear. The gender balance among members – though not among union bosses – is near half and half. Many are part-time. The changes mean that unions are weaker in almost all respects than they were through most of the 20th century. When they strike, they do not generally hit employers' profits, they simply inconvenience the public.

But unions have a strength they did not have in their heyday, in that the social gap between their members and the rest of the public has closed. In 1926, middle-class people were frightened of the black-faced miners emerging to man picket lines, because they knew nothing about them and imagined the worst. Now, those on picket lines are the sort most of us encounter regularly – teachers, government office staff and so on.

Instead of being a test of industrial muscle, the current dispute is ultimately a battle for public support. The unions lack the power to force the Government to surrender, but if they can convince the public that it is the unreasonableness of the Government that provokes them to strike, they can make the political price the Government must pay to win dangerously high.