On March 3rd, 1985, the National Union of Mineworkers, led by Arthurs Scargill, voted to return to work after a year-long strike, the longest and most bitter strike, and one that finished without an agreement. The NUM members put on a brave face, many marching back behind colliery brass bands, but they and everyone else knew that Britain's strongest union, the NUM, had been beaten.

There were many reasons why the 1984-5 miners' strike failed where previous ones had succeeded. Margaret Thatcher has seen how the 1974 strike had brought down the Heath government by shutting down power stations through picketing and secondary support by other unions, and was determined not to let this happen again. When a strike was threatened over proposed pit closures in 1981, she had backed down because she wasn't ready, with only six weeks of coal stocks.

By 1984 she was ready. Her union reforms had introduced secret ballots for leadership elections and before strike action, and secondary picketing had been made illegal, with the threat that court action could seize union funds. She had built up six months of coal stocks, made arrangements to hire non-unionized lorry drivers to move coal to power stations, converted some coal-fired power stations to heavy fuel oil, and ramped up the nuclear contribution to the energy supply.

NUM leader, Arthur Scargill, a hardline Marxist, was itching for a showdown to humiliate and bring down the government, as in 1974. The union had balloted its members for strike action in 1982 and 1983, but had failed to win a majority, let alone the 55% the rules required. In 1984, to avoid another ballot defeat, the NUM executive voted 69-54 not to hold a ballot, but to have some areas strike and picket others to stop them mining. The result was that some efficient and profitable pits, led by the Nottinghamshire ones, decided to keep working. Violent confrontations occurred as pickets tried to stop them, and mobile police units were established to bring in police from outside to thwart the flying pickets.

Nottinghamshire and South Leicestershire miners still working set up a new union, the Democratic Union of Mineworkers, and as the year wore on, increasing numbers of strikers began to drift back to work. Scargill drew fire for accepting a £1.5 million donation from the Soviet Union, and for opposing the Polish Union, Solidarity, as an "anti-socialist organization which desires the overthrow of a socialist state". The result was that Polish coal continued to be exported to Britain throughout the strike.

The defeat of the strike, on this day in 1985, ended the era of militant union domination in the UK. The political power of the NUM and other unions was much diminished, and union membership fell. It plunged from roughly 40% of Britain's workforce to barely 20%, and today barely 14% of private sector workers are union members.

That historic defeat help turn round Britain's economy. In 1984 the UK lost 27 million days of work to industrial action, the highest in Europe. By 2017 this had fallen to 276,000, about 1% of the number, putting the UK among the lowest. It severely damaged the unions' prestige and morale, as well as their influence. On the cultural front, it did inspire some movies, including "Billy Elliot" in 2000, "Brassed Off" in 1996, and "Pride" in 2014, based on the real-life LGBT group that raised money for the strikers. Funniest was "Strike" in 1998, which used the strike as backdrop to a savage satire on Hollywood.