The biggest problem with Vince Cable isn't his views on banks. It's his views on tax.

by Paul Goodman

Vince Cable's speech to the Liberal Democrat Conference, over which so much reporting ink had been spilled in advance, was crafted as a Cabinet Members' speeches usually are - not ad-libbed from notes, let alone delivered impromptu.  There were some passable jokes (on Labour: "They demand a plan B, but they don't have a plan A") and some solid soundbites ("the post office is not for sale").  The full text is here.

Essentially, the Business Secretary's address was a further demonstration of the conference's aim: to demonstrate that the Liberal Democrats are now a party of government, to keep a certain distance from their Coalition partners (though Cable was careful to name-check David Willetts)...and to get Liberal Democrat activists behind the Coalition.  "We need you," he concluded.  "We need all of you."

The speech had been trailed as an attack on banking and bankers.  Sure, there was a far-fetched analogy between bankers and Bob Crow, and Cable side-stepped government's role in the financial crisis.  But the Business Secretary had no important new announcement to make - no new crackdown on bonuses, for example - and the Treasury stlll looks to be in control in the forthcoming Banking Commission.

No, the biggest problem with Cable isn't his views on banks, but his stance on tax.  He conceded yesterday at a fringe meeting that higher taxes bring in little extra revenue, but are there to ensure that - as he put today - "the broadest backs carry the biggest burden".  He itemised for the Liberal Democrat's victories on tax: no inheritance tax cuts, the capital gains tax rise, income tax reductions for poorer workers only.

Indeed, he went further by banging on about his beloved mansion tax, regretting that it hasn't made it into the Coalition Agreement.  And he emphasised his own personal commitment to higher taxes in the form of a graduate tax of some sort, which he told the conference he was pushing for "as best I can".  Michael Moore's preoccupied with Scotland.  Danny Alexander's busy at the Treasury.

Chris Huhne's chuffed at being a Cabinet Minister and is largely confining himself to his Department.  Nick Clegg is busy helping to hold the Coalition together.  Only Cable seems able or willing (or both) to take a strong personal position on a major policy area.  Unfortunately for the Coalition and the country, it's the wrong one.  Too heavy a tax burden can break backs - broad or otherwise.