In government, New Labour actually reduced income tax - by lowering the basic rate of tax to 22% and introducing a 10p starting rate.
The thing to watch is how far – or not – the chancellor claws back the gain from the better-off by reducing the basic rate limit, at which 40% tax kicks in.
By way of illustration, the IFS said that closing the gap could be achieved by increasing the basic rate of income tax in Scotland to 29 per cent, increasing VAT to 28 per cent, or cutting public spending by 8 per cent.
Meanwhile, £2bn could be found by either increasing the basic rate of income tax by 0.25%, VAT by 0.5% or reducing pension tax relief.
By comparison, raising the basic rate of income tax by 1p brings in just £4.5bn a year.
Capital gains tax by contrast charges the basic rate taxpayer a rate of 18%, and a higher-rate taxpayer 28%.
The National Health Action party, founded in 2012 to challenge the coalition government's healthcare reforms with candidates standing in 12 constituencies, would increase NHS spending by at least 4% a year, initially paid for by a penny on the basic rate of income tax.
But further up the income scale the rise in allowances will be nullified by a reduction in the basic rate limit.
Last but not least there were tax credits, with the cuts – as in the budget – half-heartedly soothed by an increase in the basic rate for children.
Yet like Gordon Brown's disastrous abolition of the 10p tax rate – overshadowed in the headlines at the time by the reduction in the basic rate of income tax it paid for – politicians have failed to focus until the moment for implementation is near, and the tide of letters from furious constituents has started to flood in.
