The Bush administration has led the world with a supposedly "neo-con" agenda - right wing, fiercely pro-market, and anti anything that in the US can be called "liberal", what we would call moderately left-of-centre.

Yet yesterday the Bush administration launched what could end up being the world's biggest financial bail out, by taking control of troubled Fannie Mae and Freddie Mac.

Ideological? Not a bit of it. The Bush administration, like all of its predecessors, is actually ultra-pragmatic when it comes to trying to save the US financial system.

And, to give credit where it is due, the results of that pragmatism are there for all to see today.

Share prices in the City today have soared - a word rather over-used in market reporting but justified today.

Given the stakes involved, yesterday's intervention by the US Treasury Secretary Henry M. Paulson, Jr, or Hank to his friends – he could only be American with a name like that – has reassured investors.

Fannie and Freddie between them own or guarantee more than five trillion US dollars (£2,800bn) worth of mortgages. Yip, that's a fair bit of dosh.

The pair have lost more than 14 billion dollars (£8bn) in the last year due to the slumping US housing market but their collapse would cause global turmoil as their bonds are held by major investors worldwide.

Were they to have failed, the effect would have been the financial equivalent of a tsunami engulfing the world financial markets.

So the move by Paulson – which the Bush administration declined to call "nationalisation" but looks very much like it – has buoyed the markets.

The news sent Asian stock markets soaring overnight, with Japan's benchmark Nikkei 225 up 3.4% and Hong Kong's Hang Seng showing gains of almost 4%.

Here in the UK the Footsie 100 leaped by nearly 4% as investors dared to hope that this might be the end – or perhaps the beginning of the end – of what we have glibly described as the credit crunch.

Some of our largest banks can thank the Bush administration for sending their stocks surging to double-digit gains today.

At the time of writing this, Barclays gained 15% in early trading , HBoS and Royal Bank of Scotland both leapt 14%, while Lloyds TSB added more than 10%.

The key now will be to see how the US markets react when they open this afternoon – morning for them, of course.

Already the predictions are that there will be a massive hike.

Ian Griffiths a Dealer at CMC Markets says of the Fannie and Freddie move that it "looks set to give US indices a huge boost on Monday afternoon".

Griffiths adds: "It will take some big news to derail the rally and with little out on the economic calendar it could be left to a rise oil prices to oppose the move."

His conclusion is that "It seems that Uncle Sam has come to the rescue, however it will leave many waiting to see if the markets can hold on to the strong gains."

And that, of course, is the nub of it.

We will have to wait to see if today's Freddie and Fannie euphoria is maintained for more than a day.