There is still plenty at stake in the general election – even with the Tories so far ahead

For the health of our democracy we need an effective opposition, and we need it now

The Conservative gains in Thursday’s local elections, especially the capture of the new post of West Midlands Mayor in a strong Labour area, confirm the impression that Theresa May is heading for a huge victory in the general election on 8 June. It is our democratic duty to resist this assumption.

The general election campaign ought to be a chance to let the people into the great debate about the future of the country, and in particular about the choices facing the nation as it prepares to leave the European Union. If the conviction grows that the outcome of the election has already been decided, that debate will be stifled. That is why The Independent will continue to use the election campaign to ask questions about Brexit, and to try to keep the debate as open as possible about the problems of social care, the NHS, education and housing.

But for the election to be a truly democratic exercise requires the political leaders to engage with the voters. It is a pity that the Prime Minister has chosen to play it safe by refusing to take part in TV debates. Whatever the traditionalists might say, there is no better way to reach the largest possible audience.

Jeremy Corbyn and John McDonnell ought to reflect, even at this late stage, on what they are hoping to achieve by their campaign and whether they should fight it differently. They must know that most Labour MPs have resigned themselves to defeat and are already thinking about how to rebuild from the ruins. Indeed, some of them argue privately that the defeat needs to be complete and overwhelming to allow for a healthy fresh start. This is a dangerous impulse that risks condemning the Labour Party to years of irrelevance. For the health of our democracy we need an effective opposition, and we need it now.

That means refusing to accept and therefore to reinforce an image of Theresa May as a dominant, Thatcher-like figure. That will be difficult. Thursday’s votes marked the end of Ukip as a viable party. Douglas Carswell, the former MP for Clacton, drily described himself today as the party’s “first and last MP”. The party has achieved its purpose and much of its support has been absorbed by Ms May’s Conservatives.

Thursday’s elections also suggested that the Lib Dem resurgence hasn’t made as much progress as Tim Farron might have hoped. Traditionally the third party of British politics and a big force in local government, the Lib Dems lost council seats overall. This is not a great platform for the general election, but the party must still hope that the clarity of its opposition to Brexit will position it to benefit from tactical voting on 8 June.

Even the Scottish National Party, for so long the most vibrant political movement in the UK, has fallen back. The revival in Scotland is the most striking feature of the Conservatives’ strong national performance. Of the minor parties, only Plaid Cymru and the Greens made gains, and even in Wales the Conservatives made much greater advances.

The standard mantra of political analysis is that local elections are not a good guide to how people would vote in a general election. It is not completely true, but the next five weeks should be fought out as if the two are entirely separate.

Brexit is the great issue of the general election. We are faced with the prospect of Ms May being given a free hand to decide that her mandate means whatever she says it means. The voters, and journalists on their behalf, must approach the election campaign as if it were wide open and demand answers to the questions about our future relationship with the EU. We must not treat the result of the general election as a foregone conclusion.