Britain would not "collapse" if it left the EU, David Cameron declared in his interview on the Today programme this morning. It was a concession to those in his cabinet who believe that the UK should make it clear that it is prepared to withdraw if it fails to secure significantly changed terms of membership. One of those ministers, Eric Pickles, told Radio 5 Live's Pienaar's Politics last night: "If it's in our firm national interest that we should remain in the EU – and I sincerely hope that is the case – then we should stay. But we shouldn't stay at any price." Michael Gove has similarly argued that Britain must threaten to leave the EU in order to achieve a successful renegotiation.
The danger for Cameron (who remains a genuine supporter of British membership) is that unless he is able to repatriate substantial powers from Brussels, some cabinet ministers will conclude that EU membership is no longer in Britain's interests. In this week's Spectator, James Forsyth reported that there are "at least nine Cabinet members" who would be inclined to vote "out" in a referendum if Cameron only proves able to secure minor concessions such as the exemption of the NHS from the Working Time Directive and restrictions on immigration from the EU. Confronted by what Forsyth says would be the biggest Conservative split since the repeal of the Corn Laws, how could Cameron respond?
It is worth recalling how the last (and only) government to hold an EU referendum - Harold Wilson's Labour administration in 1975 - dealt with a comparable problem. With europhiles like Roy Jenkins on one side and eurosceptics like Tony Benn on the other, Wilson took the unprecedented step of suspending collective cabinet responsibility in order to allow his ministers to support either side in the campaign. Seven Labour cabinet ministers - Benn, Barbara Castle, Michael Foot, William Ross, Peter Shore John Silkin, Eric Varley - went on to unsuccessfully argue for withdrawal from the EEC (the vote was 67-33 in favour of membership).
As I wrote earlier, it is wrong to assume that a referendum is inevitable when Cameron's strategy is entirely dependent on a Conservative majority at the next election (an outcome that looks increasingly unlikely). But on the assumption that one does take place, the most elegant way for Cameron to respond to a split party may be to invoke the Wilson precedent.