Personal debt levels are a significant factor in any recession because, once the downturn strikes, individuals look to pay down debt as the prospect of unemployment, loss of orders and the like increases. So as households rein in spending and stop borrowing, a bad situation is made worse and economic output fails to recover. The banks were heavily criticized for not doing enough to boost small business lending. But, to be fair to them, the demand just wasn't there: individuals and SMEs were in no mood to borrow more money in the environment prevailing in 2009-2012.
Banks like the U.K. lender Northern Rock were quite rightly vilified for making available 100 percent loan-to-value mortgages, and the yet more risible 125LTV loan, but no-one is forced to borrow under such terms.
We have to look at ourselves too.
Read MoreUK housing boom cools amid 'mortgage prison' fears
Now of course, we've turned the corner haven't we? The U.K. housing sector, especially in London and the South East, looks like it's already overheating, the Bank of England has commented on it and the government's need to subsidize house purchases for first-time buyers (when will they ever learn?) and we may well be only another five-six years away from the next crash.
When it comes to learning lessons, the best place to start is at home.
Professor Moorad Choudhry is at the Department of Mathematical Sciences, Brunel University and author of The Principles of Banking(John Wiley & Sons 2012).