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George Osborne and David Cameron are having their first wobble, over cuts, in the face of strong attacks from Labour

For David Cameron, the moment of truth has arrived. It was always going to. It is remarkable that it has not happened before.

The Conservative Party is having a wobble. Not about Mr Cameron's leadership. Not really about policy. It is wobbling because it is not used to a united Labour Party turning its guns on the enemy instead of itself – or, more likely, its leader. Nor do the Tories seem prepared for the media spotlight that was bound to fall on them once the general election approached.

I am surprised that the Tories are surprised. Perhaps it tells us something about their inexperience in campaigning. Their...