I suspect Darling does, but is keeping schtum for political reasons, and I'm pretty sure Vince is doing the same. Why would they both do this? Y'see, unless my understanding of economics generally is completely off base (and I've been trying to do a lot of understanding of economics over the last 5 years), increasing National Insurance does cost jobs. Channel 4 FactCheck certainly think so. Here's why:
( It's all about Tax Incidence and Marginal Costs )
( It's not about the overall tax bill )
( Tax incidence: who pays )
Note that when Vince has attacked the Tories on this, he's not argued with them too much over the NI stuff; he's argued with them over how they're going to pay for it; he's right to say that the money they're using is pretty much fictional, from what I can tell.
The "a price worth paying" argumentWhat the Govt could, and perhaps should, be doing is actually admitting that there will be a small decrease in the rate of fall of unemployment (which is basically what the above means), but that the greater economic stability makes us all better off medium term, etc etc etc. Y'know, the "a price worth paying" argument. Except that doesn't tend to go down well with the Trades Unions, who, well, are bankrolling their election campaign.
And I'm not sure, myself, that it is a price worth paying, there are better ways of raising money; capital gains tax taper relief anyone?