Forget the synthetic fury about campaign contributions. Who but the breathless BBC cares about whose brother-in-law wrote a campaign cheque for Alan Johnson? Tune out. Obscured by such tabloid journalism, a serious political argument is taking shape. New dividing lines about the reach of the state are marking out the ground for the next general election.

The running so far has been made by David Cameron. The Tory leader has dropped the slash-and-burn approach to government of his predecessors. Much to the chagrin of those on the right of his party, he is promising only incremental tax cuts. For its first few years, a Cameron-led government would be pledged to stick to Labour’s spending plans.