Margaret Thatcher’s political triumph in 1979 is often seen as an inevitable result of shifting economic and social trends. However, it was at least partly down to a fatal miscalculation on the part of the Labour prime minister James Callaghan.
The defection of two MPs forced the Labour government, which had won a majority of only three in October 1974, to enter into an informal agreement with the Liberals, which expired in the summer of 1978. With Labour leading in the opinion polls, everyone expected Callaghan to call, and then win, an early autumn election.
Instead, Callaghan shocked everyone by deciding to wait until the following year, when he assumed that the economy would be stronger. At the start of 1979, the economy was hit by a wave of strikes by workers angry at government attempts to limit wage increases as a whole to 5% (well below the rate of inflation). Large segments of the public sector, including grave diggers and refuse collectors, took part in these strikes.
Against the backdrop of a freezing winter, this led to widespread public anger, magnified when an inept response to an interviewer gave the impression that the PM was not taking the problem seriously.
Trailing in the polls, Callaghan attempted to plough on until the autumn, hoping that public opinion would shift back in his favour. However, the loss of referendums on Welsh and Scottish devolution led to the SNP throwing its support in favour of a no-confidence vote. Matters came to a head at the end of March.
In the end, Labour lost by one vote, because one of its MPs was unable to travel from hospital (he died a few days later). This forced an election in May, which the Conservatives won decisively, in part owing to a campaign focused on curbing the power of trade unions.