To try and put the headline figure of £10bn into some sort of perspective, here is an extract from a report on the invasion and occupation of Iraq from the Global Policy Forum*. (It is my emphasis in the following quote).
The costs incurred by other Coalition members for their contingents should also be taken into account, but the calculation exercise is exceedingly difficult, given the many small contingents and the hidden budget numbers for many participant governments. The biggest of Washington ‘s partners, the UK , offers some glimpse of other Coalition costs. Though the UK government has hidden its Iraq expenditures and did not make them available to Parliament or the public, researchers using the Freedom of Information Act discovered that the UK had spent about £4.5 billion (about $9 billion) for its military involvement in Iraq as of late 2005.  According to some estimates, and in spite of substantial draw-down of forces, each additional year in Iraq will cost the UK treasury an extra £1 billion.  So UK costs as of late 2006 would total about $11 billion. Such budgeted figures do not take into account costs such as refurbishment or replacement of military equipment that the British Ministry of Defence will eventually have to cover.  Nor does it take account of the many other long-term costs including death benefits and health care costs for veterans
So, Halifax Bank of Scotland lost about £10bn during 2008 which is roughly equivalent to the UK expenditure on the invasion and occupation of Iraq between 2003 and 2006. The Government encouraged Lloyds TSB to ‘save’ HBos in th autumn of 2008 through a bank merger – and this happened, however, the new unified Lloyds banking group is now liable for all of this inherited HBoS debt.
* Who are the Global Policy Forum? See here, this quote is from their about us page.
Global Policy Forum’s mission is to monitor policy making at the United Nations, promote accountability of global decisions, educate and mobilize for global citizen participation, and advocate on vital issues of international peace and justice.