It was Sian Berry, the Green candidate for London mayor, who told me - a while back - that people care less about the environment during difficult economic times.

“In about the mid-1980s, environmental issues started to appear spontaneously, and it kept rising up to 1989,” says Ms Berry. “At the top of the economic cycle it was considered more important than health and immigration. During the recession it dropped like a stone.”

There is even a word for it: Maslow’s theory (look it up on Google).

Hilary Benn, environment secretary, will tackle the theme in a speech tomorrow in Washington.

“Some will say that these pressures mean that we must put our economic interests first - that we must choose economic stability over environmental stability. We need both. So I believe that this is a false choice….” he will say.

“We must resist temptation to put off dealing with climate change for another day, when the world economy is stronger.”

But there is growing evidence that green issues are sliding down the policy priority list; the lukewarm path to bin taxes and road taxes…the possible cancellation of autumn’s fuel duty rise…

Nor are the Tories banging the green drum any more. There was little or no mention of the environment in David Cameron’s big policy speech last week.

A tea-spluttering moment this morning when I read Anatole Kaletsky in The Times. 

Until recently the paper’s economics guru was a bull on the UK economy/housing market (accurately as it turned out).

Today, perhaps inspired by the latest IMF report, he was talking about price falls of up to 30 per cent.

 You might feel sympathetic towards Gordon Brown at this point. Why should he take the political flak for any downturn?

Here are three reasons which come to mind:

1] Changing the Bank of England’s inflation target from RPI to CPI (which does not include house price inflation). This enabled the monetary policy committee to cut interest rates much further in recent years. This allowed people to borrow more. Boom.

2] Shifting planning guidelines for new homes from greenfield to brownfield. Though well-intentioned, this has led to a glut of city centre flats, bought mainly by buy-to-let investors. Fingers will be scorched.

3] Rhetoric. Policies, speeches and initiatives have been laced with the presumption that house prices were a one-way bet. The target for home-ownership was upped to 90 per cent (why have one in the first place?).

Even now, the government is “helping” low-paid public sector workers risk what meagre savings they have getting on the housing ladder……as if this can only be a good thing.