By Mark Wallace
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It's obviously important to establish properly agreed spending plans for each department through the Coalition's full term in office. But there's also a hefty political element on the Chancellor's part – as can be seen by the chaos it has thrown the two Eds into, unable to decide whether they'll spend and borrow less, spend and borrow more or insist that both are possible.
That political motivation is also true of some of the Cabinet. It is telling that Vince Cable was the last one to agree a deal with the Treasury, and the very public manner in which he did it. James Forsyth of the Spectator was not alone in being briefed that the talks would last late into the night on Tuesday (though in practice they ended late yesterday).
Those who are sceptical of the Lib Dem Left's commitment to the Coalition – and let's be honest, the list of those who aren't sceptical would be a lot shorter – rightly see this as posturing rather than a genuine delay in negotiations. The question is who Vince intends his audience to be.
There's undoubtedly an element of public foot-dragging to reassure dissatisfied Lib Dem members and voters. But there is also a message squarely aimed at the Labour Party.
Think back to Vince's hilariously wonkish New Statesman article in March. There were plenty of academic citations and technical flourishes wielded in an effort to demonstrate his intellectual prowess – but the underlying message was direct. He wasn't apologising for supporting Coalition austerity so far, but he was arguing that now on the correct approach would be that of Ed Balls.
While he's always been a long way from being an Orange Book Liberal, it now appears that this is part of a much bigger play. By first mooting a debt-funded fiscal Plan B and now ensuring he is seen to be the last minister dragged to the table by George Osborne, Cable is positioning himself to inherit his party's leadership in a Lab/Lib coalition. He seeks to be an acceptable partner for Labour should they need one – a resistance fighter rather than a willing collaborator.
Given such games, Nick Clegg would have good reason to be more annoyed than George Osborne about Vince's approach to the spending negotiations.