The Labour Party, like the Conservatives, has committed to borrow only to invest, to fund current spending only from current income, and to get debt as a percentage of GDP down. As ever when it comes to fiscal rules, the devil is in the detail, and these rules are less than they seem. Labour acknowledges that this may take some time, but its promise is that it will meet its fiscal rules by achieving the highest growth rate in the G7.

As with the Conservatives, Labour knows that these fiscal rules leave plenty of wriggle room. The deadline on current spending bites only gradually and that for the debt to be coming down is by the end of its first Parliament. More importantly, current spending on desperately needed capital maintenance could be renamed as “investment” expenditure (as Gordon Brown did with education and health spending), leaving the next generation to pick up the tab for what should come out of current income. For both parties, “growth” is assumed to help fix the problems, with Labour targeting the highest growth rate amongst the G7 by the end of the Parliament. Neither party has any plans to tackle the lack of domestic savings, and hence the almost complete reliance on foreigners to lend them the money.

The fiscal rules allow large scope for fudge. If either party really meant to be fiscally credible, it would need to be willing to entertain either serious tax rises or serious reductions in spending (or both). Fiscal rectitude is easier to announce than it is to deliver.