It's odd how ordinary house buyers can't get tax relief for mortgages (and nor should they) but banks can:

Merrill Lynch is unlikely to pay corporation tax in the UK for several decades after $29bn (£16bn) of losses suffered by the US investment bank were charged to its London-based subsidiary.

The figures, published in Merrill's regulatory filings, emphasise how the meltdown in the US subprime mortgage market is undermining tax receipts for governments far beyond America's borders. They also offer a rare glimpse into the tax management policies of a global financial institution.

Don't doubt that at the end of the day sub-prime will cost more in tax lost than Northern Rock might ever do.

It's a sobering thought.

And all the subsidy does of course go, in effect, to those who need it least. Bankers aren't losing their homes. Nor will most of those who own banks. It's ordinary people who are losing most.

It's another case of redistribution through the tax system.