Chris Matheson (There is no leftwing justification for Brexit. We must fight it to the last, theguardian.com, 7 January) thinks the world has moved on since Tony Benn, but his own picture of the world is almost exactly the picture that the original advocates of entry into the Common Market believed in in the 1970s: that the globe is divided between Oceania and Eurasia (sorry, we meant the US and the EU), and that the poor little UK has to choose between them. Benn rejected this then, and socialists should reject it now. There is a profound distinction between globalisation and internationalism, and it is one that Chris Matheson does not make.

What Matheson’s arguments boil down to is the following: (a) in a globalised world, economic and social policies have to be decided at a supranational level; and (b) membership of the EU prevents a Conservative government from implementing some of its possible policies. The problem with (a) is that it is a fantasy that the EU will implement the kinds of policies that socialists might want, given its fundamental character as a free market, with the four freedoms enshrined in a constitutional order that there is no way of changing short of a set of new treaties. Democracy is a better bet.

As for (b), be careful what you wish for: structures that impede Tory policies are just as likely to be used against socialist ones, and frequently have been. Ultimately it is not up to any of us to decide on the matter, but up, in the end, to a constitutional court whose decisions (unlike those of the UK supreme court) cannot be overriden by any political or legislative process. It is the hazard of tying our future in fundamental respects to this structure that motivates us to support a clean break with the EU.

Richard Tuck Professor of government, Harvard University, Maurice Glasman Labour, House of Lords

• My Labour colleague Chris Matheson is wrong to dismiss the long and principled history of leftwing opposition to the European Union and its predecessors.

Labour politicians as different as leader Hugh Gaitskell and Tony Benn based their opposition to this European project on sound principles of sovereignty and democracy. Gaitskell famously told the 1962 Labour conference that joining the Common Market “would be the end of Britain as an independent European state” and Tony Benn, referring to the European commission, argued that if we can’t “get rid of you, we don’t have a democracy”.

Since the Enlightenment it has been the commonly held belief of the left that those who decide on our laws and taxes should be able to be removed by the electorate; the EU does not allow this. The left was also united against Margaret Thatcher’s monetarist policies, which put 3 million people out of work in the UK. This was one of the tools used to weaken trade unions.

Why on earth should we now support the EU, which has the EU stability and growth pact at its core? This is Thatcherism internationalised, and the resulting deflation has put a generation of young people on the dole across the whole of Southern Europe. The EU damages the economy as well as democracy.

Chris Matheson voted in 2015 to hold the referendum and on 1 February 2017 voted to give the prime minister authority to trigger article 50. Chris was right then to give people the power to decide our future in a referendum and to respect the result. He is wrong now to deny both the long tradition within Labour to oppose the EU and his own voting record. The voters will never trust us again if we don’t honour their decision.

Graham Stringer MP

Labour, Blackley and Broughton

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