David Cameron has just been interviewed by Sarah Montague on Radio Four, who rather put him through his paces. She teased out an interesting position he is adopting to the growing concern about his Help to Buy mortgage subsidies. He defends himself by saying he will liberate those ‘trapped’ in rented accommodation and casts his critics as cold-hearted rich kids.

Montague started by saying that Cameron is putting £12 billion behind this and yet…

It’s hard to find almost anyone who thinks it’s a good idea. The Treasury Select Committee. The former Bank of England governor, Sir Mervyn King. The IMF. The Council of Mortgage lenders. We could go on to think tanks: the Adam Smith Institute, Policy Exchange.’

This is a pretty damning list, and you could add to it. It’s hard to find any sane economist who thinks that a British version of Fannie Mae is a good idea.

‘I would argue: you need to get out more and listen to ordinary people who want to buy a home who can afford mortgage payments. They’ve got good jobs but they can’t get a mortgage… Because of the damage done to our banks they are not offering the 90-95 per cent mortgages which have been part of our life for many many years.’

Really? The 95pc deals are certainly harder to find (the Bank of England has stopped collecting data on them). But for those with 10 per cent deposit, the BoE says teh average rate is 4.52pc, down from 6.44pc five years ago. Some, like Stafford Railway Building Society, are offering to lend at 3.6 per cent. It’s not clear that the ‘market failure’ – or need for state intervention – is as acute as Cameron suggests.

He then moves to a new problem: the oppression of having to rent. This really is a new one on me.

‘Currently they are trapped in rental accommodation, paying high rent to somebody else for their home.’

Trapped? Really? At this rate we will be sending foreign aid to Austria, Denmark the Netherlands, Korea and Sweden as well as France and Germany. Most people in these countries rent, perhaps unaware that they are ‘trapped’.

At the end, Cameron whipped out the class card again:

‘I don’t want to be the Prime Minister who stands aside and says: you can only buy a flat in this country if you have got rich parents.’

 Of course, Cameron and most of his Cabinet colleagues all have rich parents and many didn’t even need a mortgage to get their first home – a point Labour makes from time to time. So perhaps this line is intended to protect them from this political attack.

‘The problem is too much debt,’ said Montague. ‘And you’re encouraging people to take on more debt.’ No, said Cameron, ‘the problem was 110 per cent mortgages.’ Not what he was saying about ten minutes earlier: then, he did indeed say that the problem was too much debt.

Then, she moved to what is – for me – the killer point.  ’You were very critical about Ed Miliband for interfering in the energy market in the way that he did. What is different about interfering in the housing market?’

‘The big difference today is that the mortgage market isn’t working… there is a market failure here which the government is trying to correct which will help hard-working people.’

But this – market failure – is precisely what Miliband says about the energy market. Having trawled the bars last night, I can tell you that many Conservatives believe their position is identical.

Tags: BubbleWatch, David Cameron, Help to Buy, UK politics