The issue of Europe has split the Conservative Party for decades – so what happens now?

Europe has divided the Conservatives since the 1950s, when the British first posited the idea of joining a new European economic community. Initially opposed to the concept, they then changed their minds to become the party of Europe in the 1970s and 80s, before changing them back again in the 2010s, ending up as the party of Brexit.

Now Rishi Sunak has won an improbable deal with the EU over the Northern Ireland protocol, which means that something like peace in the eternal Tory civil war may be at hand... but a number of questions remain.

How does Sunak’s Windsor Framework compare with the efforts of his predecessors?

It’s a much smaller business than, say, the Treaty of Rome (ratified by the UK in 1972), the Maastricht Treaty (1993), or the EU-UK trade and cooperation agreement of 2021 (of which the NI protocol is a part), but the Northern Ireland protocol has proved to be the most intractable of all the many difficult aspects of Brexit.

Even now, not all of the contradictions and uncertainties have been resolved, but it does seem that Sunak, and the EU’s officials, have got as close as humanly possible to ensuring that two and two make five. The irony is that Sunak – who, unlike Boris Johnson, is a sincere and long-standing Leaver – has managed to succeed where Johnson failed, and to place UK-EU relations on a friendlier, more secure footing.

Is the Tory civil war on Europe over?

No. For some, the existing arrangements are intrinsically unsatisfactory, because of both the special arrangements for Northern Ireland and the remaining obligations included in the Brexit treaty, such the “level playing field” provisions on the environment. Only a complete break with World Trade Organisation trading terms, and a conventional hard economic border on the island of Ireland, would be satisfactory.

Have all Conservative prime ministers or leaders been Eurosceptic?

By no means. Most came to terms with Europe, and tried to make it work. The most outstanding example of that was Margaret Thatcher. Despite her bickering with other leaders about budgets, and an innate Euroscepticism, she campaigned for the UK to stay in Europe in the 1975 referendum – and, even more significantly, pushed for the creation of the single market, from 1986 to its partial completion in 1992.

That included a dilution of the national veto. It was the UK’s abiding contribution to the European project, even though it is reviled by the Europhobes of today.

Ted Heath, the man who finally got Britain, together with Ireland and Denmark, into Europe in 1972, was the most prominent and dedicated “European” in British politics ever. Heath dedicated his political life to the cause. He understood Europe to be a political enterprise, and one that was essential to preserving peace on a continent that had been through two world wars in the first half of the 20th century.

Heath was Harold Macmillan’s chief negotiator for the first, unsuccessful application to join in 1961, when the French president Charles de Gaulle vetoed the application. De Gaulle was suspicious that the British would act as a “Trojan horse” for the Americans, whose entry would threaten France’s political leadership of what was then a smaller group of six Western European powers.

Only after de Gaulle was out of the picture, and Heath became prime minister in 1970, was it possible to persuade European leaders that the UK would be a sincere believer in integration, not a permanently grumbling passenger on a journey towards a European unity in which it didn’t really believe.

What are the arguments within the Conservative Party about?

Outlook, money and power. Historically, the UK – with its empire, Commonwealth, and “special relationship” with the US, not to mention its distinct maritime, political and legal traditions – has often regarded not just “the continent” but the world as its oyster. In a quotation often attributed to Winston Churchill, if faced with the choice, Britain would always choose the open sea.

More prosaically, the original EU was set up to protect French and German farmers, whereas Britain had traditionally sourced its food and raw materials from around the globe. The taxes on imported food and the structure of the European budget did mean that Britain, by no means its richest state, was a hefty net contributor – hence the famous exaggerated claim on the side of the Leave campaign bus that membership of the bloc “cost” £350m a month.

Then there is the matter of power – or rather, “sovereignty”. This belief in absolute national, parliamentary sovereignty is something that has extended across the parties, and was stronger in the past in the Labour Party – Tony Benn and Michael Foot were dedicated, romantic believers in the democratic mandate of the Commons.

Among the Tories, the same arguments from decades past are still heard today – that no one, not even a prime minister or a parliament, could give away the historic and permanent status, rights and prerogatives of the Commons. Figures such as Heath and the pro-Europeans argued for shared or “pooled” sovereignty, so that while “Europe” had more say over what happened in Britain, Britain in turn had more say over what happened in Europe.

The great irony is that by the time the 2016 referendum came around, the European Union was in many ways shaped to suit the British agenda. It had deepened the single market, welcomed the Nordic and Eastern European nations (which often sided with the British in disputes), and the impetus to “ever closer union” was slowing – David Cameron managed to get that watered down in his abortive 2016 “renegotiation”.

The UK had negotiated opt-outs from the parts of the EU project it most disliked, such as the euro, as well as a budget rebate. The eurozone had big problems, but the UK was insulated from the worst of their effects. All in all, it was a pretty decent deal – and the dreaded federal “superstate” was less of a realistic prospect than ever.

How many Tory prime ministers has the European question helped to bring down?

Almost all of them, to a greater or lesser extent, starting with Harold Macmillan. He had set his mind on membership of the dynamic, fast-growing European Community as a way of reversing Britain’s relative decline. It was really the centrepiece of his government’s economic strategy, and the French veto of 1963 therefore effectively wrecked it. The very obvious humiliation at the hands of de Gaulle contributed to the Conservative defeat in 1964.

In the case of Ted Heath, his fall from office in 1974, and from the party leadership a year later, was mostly to do with a string of economic calamities, and it’s fair to say that joining the European Community (or “Common Market”) wasn’t universally popular. But it was Enoch Powell’s intervention, advising Tory voters to opt for Labour because it was offering a referendum on staying in, that swung enough of the marginal seats in the West Midlands Labour’s way and so deprived Heath of victory.

It was splits over European policy and the option of joining a new European single currency that helped to push Margaret Thatcher out of office in 1990. John Major managed to survive even deeper splits over the Maastricht Treaty, but the struggles to get the treaty passed were debilitating: in one key vote, he had to rely on Paddy Ashdown and the Liberal Democrats to prevent the fall of his government.

Major’s administration and party looked hopelessly divided, which probably added to the depth of the defeat in 1997, with the intervention of James Goldsmith’s Referendum Party stirring things up.

The loss of the 2016 EU referendum ended Cameron’s career abruptly, and Theresa May’s failure to get Brexit done saw her lose her majority in the 2017 snap election. She would end her time in Downing Street in 2019.

Johnson, ironically, is the only Tory prime minister to have turned Europe to his advantage, launching his assault on the party establishment in the referendum and using the promise to “get Brexit done” to win his near-landslide majority in the 2019 election. Yet his botched deal might well have caught up with him in the end.

Will the infighting over the issue destroy Sunak?

Unusually, it shouldn’t – and it may well boost his reputation and actually help him to survive as leader. In a sense he is lucky that it has come when it has, after six years of more or less continual civil war in his party and often bitter arguments in the country.

Britain is heartily sick and tired of Brexit, and wants nothing more than some peace and quiet. Even those who dislike Sunak’s deal will probably put up with it out of sheer exhaustion and for lack of alternatives. That is why the announcement of a fairly prosaic set of detailed and relatively modest changes to trade arrangements in Northern Ireland is being greeted in a number of quarters like VE Day.

No one, however, could be less happy than Johnson, who failed where Sunak has succeeded. How long the relative peace holds is difficult to say. Talks about fishing quotas will begin again in a couple of years...