Analysis: Cameron’s referendum tactics reveal a deep, deep weakness

Eurosceptic troublemakers have forced David Cameron into a reluctant equivocation which collapses under scrutiny. By refusing to listen to them, they are making him play a terrible political price.

No 10 faces a nightmare this week. David Cameron is burying his head in the White House. He's trying to ignore Tory turmoil over Europe which, as Malcolm Rifkind rightly pointed out this morning, threatens to cost the Conservatives both votes and party unity.

In a sailing boat, there are no brakes. Once you've hoisted a sail the ship will keep ploughing forwards. Just as David Cameron has set off on a lengthy voyage towards an EU referendum in several years' time, he doesn't really have an emergency stop when sudden gusts come along.

On a sailing boat, you cope with squalls by releasing tension from the sails. Ropes which had been pulled taut are released and become slack, reducing the effectiveness and therefore the speed. This week Downing Street is trying to do exactly that on the EU referendum issue. Like many reluctant mariners, it can only do so much.

The rope No 10 has chosen to relax is the tautness of its whipping arrangements. Cameron is allowing ministers to abstain from the vote on the amendment, which is now set for Wednesday evening (they are still forbidden to back the eurosceptic amendment, however). Parliamentary private secretaries, those ministerial bag-carriers hoping for promotion to a more meaningful rank, are being allowed to rebel.

"We are in a coalition government and that does change things somewhat," the prime minister's spokesman said. It is hard for Tory ministers, he explained; a referendum is, after all, "Conservative party policy". The subtext is that their discomfort is only to be expected.

The premise of this argument is all wrong. Conservative party policy is not so rigid it springs from the 2010 election manifesto alone. Cameron is the party leader and restated his policy in no uncertain terms in his January speech. Trying to pretend otherwise is an act of wilful blindness.

What No 10 is trying to divert you away from realising is that this is nothing to do with the coalition. The Liberal Democrats haven't even been formally asked whether they'd like to pass legislation for a referendum in the next parliament. If that exchange was conducted publicly, it might become easier for a distinctive Tory position to emerge. That is the big missed trick which should have been No 10's response to the row.

The growing list of Tory ministers who would leave the European Union now is another red herring, too. Michael Gove, Philip Hammond and others can hold that view while supporting the approach to the issue Cameron has laid out. Their tantrums are well within the bounds of his strategy; they should even be viewed as reinforcing his proposition that EU-British relations require a critical renegotiation, and pronto.

Without a genuine coalition excuse, this becomes a party discipline problem of the highest order. Wednesday is about backbench MPs obeying the policy laid out by the party leader – or not.

This matters to Cameron's team. Now, you might think the flexibilities of coalition offer greater opportunities for Cameron and his staff. The amendment this week challenges the government's policy in the Queen's Speech. Normally that would amount to a firm rejection of the government's view. So No 10 is proposing to let backbenchers and even PPS' let off steam, but will ignore what they have to say.

It's true that Queen's Speech votes are not as important as they used to be. They can no longer be regarded as confidence votes in the government, thanks to a clear definition of what constitutes such a division in the coalition's own Fixed Term Parliament Act. A defeat in the Commons, for example, could be spun as a side-effect of the 'new politics'; it doesn't mean anything, Cameron could say, so why get so worked up about it?

If that was true, there would be no problem with ministers backing the amendment. They can't possibly be allowed to do that because it would put the government of this week in opposition to the government of last week that came up with the Queen's Speech. Such a move is unthinkable for ministers. It should be equally unthinkable for backbenchers, too.

This is not the kind of flexibility coalition politics is meant to create, because it has nothing to do with the coalition. It is to do with members of the Conservative parliamentary party accepting the policy of the leader – or not. On Wednesday they will vote en masse against his approach.

Tory eurosceptics will rebel on Wednesday, whether it is labelled a rebellion by Downing Street or not. It makes little difference. The ministerial abstention reveals the weakness of the prime minister's hand. It confirms the free vote for Tory ministerial aides and backbenchers is a sign of weakness. As Downing Street continues its smoke and mirrors operation this week, nothing should obscure that basic, fundamental fact.