By the early 1970s there were 12 million trade unionists, organised by a network of 300,000 shop stewards.
The political ferment of 1968 – when France exploded and liberation movements grew internationally – had started to translate itself into workplace militancy in the early 1970s.
The Tories took office in 1970 and battled with the working class for the next four years. States of Emergency were called, with electricity and petrol rationed to three days a week.
The hated Industrial Relations Bill, a package of anti-union laws targeting shop stewards, sparked to a wave of struggle.
Millions struck and hundreds of thousands marched as part of the campaign to “kill the bill”.
This eventually led to five dockers being jailed in 1972, only to be freed when there was a national dock strike in their defence.
The left played a central role in building the unions and resistance to the bosses’ attacks. The Communist Party was at the heart of the strikes and the arguments over tactics.
But it put its faith in efforts to change the unions by changing their leaders. This was – and is – known as a “Broad Left” strategy.
Getting left wing union leaders elected could make the unions more likely to fight – but it didn’t guarantee that they would use the tactics necessary to secure victory.
Left wing transport union leader Jack Jones and left wing engineering union leader Hugh Scanlon became known as the “terrible twins”, and were pilloried in the press. But they instructed their members to cross electricians’ picket lines in 1973.
Yet at the same time, right winger Joe Gormley led the miners’ strikes of 1972 and 1974, which paralysed the country.
It was the level of anger, confidence and organisation of rank and file workers – the pressure from below – that was the decisive factor in whether or not union leaders would use the militant tactics necessary.
So while the Communist Party looked for leaders to back, the International Socialists – forerunner of the Socialist Workers Party – threw itself into building rank and file networks.
The confidence of the workers’ movement fed into the generalised political crisis of the Tory government.
In 1974 the Tories called an election, with the slogan “Who rules Britain?” It posed a choice between the Tories and the unions. The Labour Party won.
The level of industrial struggle started to decline, partly because of the unions’ link to Labour.
They looked to the new government to solve the problems caused by the onset of the huge economic crisis.
Labour chancellor Denis Healey had promised to “squeeze the rich until the pips squeak”. But that was not what he did in power.
The government was squeezed by the International Monetary Fund after it took a £2 billion loan with austerity conditions attached.
It demanded that workers take wage freezes, leading to cuts in living standards. Public spending was slashed and unemployment soared.
By the end of the 1970s, the union leaders could no longer hold workers back from fighting, and what came to be known as the “Winter of Discontent” began. Millions struck in an effort to break the pay freeze.
But the strikes were characterised by political confusion. After all it was the left union leaders that had justified the pay cuts as necessary to defend “our” Labour government.
This argument was carried across the movement by their Broad Left shop stewards.
The strikes were defeated – and so was the government. Margaret Thatcher came to power in 1979 and launched wave after wave of attacks.
Although there was some inspiring resistance to Thatcher – in particular the Great Miners’ Strike of 1984-5 – we are only now starting to see signs of recovery inside the working class from this period.
The lesson of the 1970s is that, although it is vitally important to campaign and elect left leaders, it is political suicide to solely rely on them.
Union leaders exist to negotiate on behalf of workers and in times of struggle are used by the right to deliver shoddy deals.
And they are even more likely to lead workers to defeat when they are tied down by loyalty the Labour government.
Today, as the debate rages about unions funding the Labour Party, and a Labour government once again bails out capitalism and expects ordinary workers to pay for it, this lesson is as relevant as ever.