President Obama is spearheading a tax shake-up
Ireland and the Netherlands are two countries which could fall foul of President Obama's plan to crackdown on tax havens.
For many years, some of the best-known American companies in the world, including the software giant Microsoft have maintained large operations in European countries with low corporate tax rates.
President Obama claims current US tax law for American corporations has created a system where "you pay lower tax if you create a job in Bangalore, India than if you create a job in Buffalo, New York".
The argument centres on what are known as "tax deferral rules", which make it more expensive for American companies to reinvest overseas profits at home than abroad.
Now tax experts are warning that President Obama's proposals will make many American corporations reconsider their overseas investments - and that this could be very bad news for Ireland and the Netherlands.
Currently, an American company which invests in Ireland pays corporation tax on its profits there of 12.5% to the Irish government.
In the Netherlands, the rate of corporation tax is 25.5%.
As long as the American company never brings the profits home to America, that's the only tax it will ever have to pay.
Until now, that's been a big disincentive to ever bringing the profits home, where the corporation tax rate is more than three times that of Ireland's - at 39.25%.
President Obama sees that as a loophole and believes that by closing it, he will raise an extra $60bn in taxation over the next five years for US government finances.
John Christensen, from the UK-based pressure group the Tax Justice Network, says action is long overdue.
"This will start to undermine the tax advantages that countries used for booking profits offshore like the Netherlands and Ireland offer to the American companies that use these places.," he says.
"These countries are tax havens - not in the traditional sense, of offering secretive banking like Switzerland or the Cayman Islands - but in terms of offering facilities for profit shifting to international corporations.
"It's just the start - and it's clear that Obama will go a lot further".
But Charles Cain, the chairman of the CM Skye investment fund, which is based on the Isle of Man says the United States will ultimately be the country that suffers most.
"If Obama's plans go through, US corporations will find a way to move out of the US altogether, so as to avoid the problems," he says.
"In so doing, probably Ireland and the Netherlands will be net beneficiaries".
The Irish Government told the BBC it would monitor the progress of any legislation carefully, and says it has sent a senior executive to its embassy in Washington to engage with the US administration and Congress.
As the global recession deepens, the US government, is keen to gain a bigger slice of the profits which multinational corporations keep in so-called tax havens around the world in order to pay for spending commitments at home.
But it is likely to win few friends in Ireland or the Netherlands by grouping them with Bermuda as "small, low tax countries" that supposedly account for a disproportionate share of the foreign profits of American companies.