Obama to break up banks
Banking reforms do not come bigger than those proposed today by President Obama.
In an echo of the break up of banks that was imposed in the United States after the Great Depression, he wants a limit on their overall size and he also wants them banned from three activities that in recent years have been central to many of them.
He is pushing for them to be prohibited from involvment in hedge funds, from buying and selling whole companies in what's known as private equity and from buying and selling securities for their own benefit on so-called proprietary trading desks.
In simple terms, he wants to prevent banks from taking speculative risks to generate colossal profits, while knowing that if their bets go wrong taxpayers will pick up the bill.
It means that some of the biggest banks in the US - from Bank of America, to JP Morgan and even Goldman Sachs - may have to be broken up.
Of course its possible (perhaps even likely) that pure investment banks, such as Goldman Sachs, will be largely exempt.
But President Obama did not say that the reform would only apply to those banks with a retail presence, such as JP Morgan and Citigroup (although perhaps it is what he meant to say). He said it would apply to "banks" as defined in US law - and Goldman became one of those in the autumn of 2008.
The big banks will hate his proposals - and will doubtless use their formidable lobbying power and financial resources to persuade Congress to water down the reform plans.
But Obama is up for the scrap. "If these folks want a fight, it is a fight I am ready to have".
The US President believes that banks are back to their bad old ways too soon after their woes led to the biggest bank global bail out in history.
Goldman Sachs would deny this, but its near record revenues of $45bn for 2009 and 50% rise in staff pay to $16bn - or $500,000 per head - shows that the banking crisis, for it at least, is a dim and distant memory.
George Osborne, the shadow chancellor, has just told me that Obama's plan to break up the banks is consistent with the views he expressed in his recent bank reform paper.
His condition for implementing such a radical plan was that it needed international agreement.
Well, he has got that now. So he has told me - explicitly - that a Tory government would impose an identical dismantling of British banks to those suggested by President Obama.
Which will generate profound fear in the boardrooms of Royal Bank of Scotland and - more especially - Barclays.