“Sunny Jim”, the unflappable son of a sailor, became Labour Prime Minister in 1976. He took over the helm from Harold Wilson, who had left HMS Britannia in some choppy seas. Big business, unhappy with the economy, had shifted money abroad, driving the pound into a downward spiral. Dole queues had tripled in length in two years, with 1.6 million people unemployed.

Those still in work were enduring pay curbs, while roaring inflation eroded their weekly pittance even further.

Callaghan sent his chancellor, cloth cap in hand, to the International Monetary Fund for pound;2.3 billion to prop up the pound. The loan came with strings attached, strings that cut deep into public services.

Council-house building virtually stopped. Hospitals were shut, and teachers lost their jobs. Union leaders backed the Government, but their members were feeling betrayed.

By the autumn of 1978 Labour’s pact with the Liberals had collapsed.

Perhaps it was time to go to the country. After all, the economic news was not all bad. Inflation had fallen and the public, at least those who were relatively well off, had faith that Callaghan could hold the pay line. So Sunny Jim announced that he would not call an election - yet. He wanted time to prove to voters that his economic policy was a success. This was a terrible mistake.

The winter of discontent erupted when the tanker drivers walked out. They wanted pound;65 for a 40-hour week, fed up with wages so low that they had to sleep three to a room in grubby hostels on their overnight stops. The lorry drivers followed suit. School caretakers, binmen, ambulance drivers, sewage and water workers, and, briefly, grave diggers all downed tools. At one point, 1.5 million public-sector workers were on strike. It was a bitterly cold winter. By late spring Margaret Thatcher was Prime Minister.