Question re Tax Havens

[Christa]

I am having a discussion with someone re tax havens.

Apparently Obama wants to crack down on off shore tax havens when he takes office. I found this article in The Guardian:

President-elect Barack Obama plans to crack down on international tax havens, including Jersey, Guernsey and the Isle of Man, within weeks of taking power in January, putting him on a collision course with Gordon Brown.

There is growing international pressure to outlaw the secretive practices of tax havens as a key part of reforms to the world's battered financial system, as the leaders of the world's 20 most powerful economies gather for a major conference in Washington next weekend.

Britain has been notably lukewarm, but Obama, whose approval will be key to any reform package over the next 12 months, was one of the signatories of the Stop Tax Haven Abuse Act, legislation put to Congress last year that blacklisted Jersey, Guernsey and 32 other jurisdictions. Key aides to Obama said he will introduce a similar law as part of a wide-ranging revenue-raising and tax-reform package, within weeks of taking power.

Obama advisors estimate the measure could raise at least $50bn (£32bn) per year in lost US tax revenues, and Washington sources say leading accountancy firms have already hired lobbyists in anticipation of a fierce battle to water down the proposals.

Key measures are likely to include: revealing the beneficial owners of secretive trusts; prohibiting accountants from charging fees on specific tax services; and identifying 'offshore secrecy jurisdictions' that 'unreasonably restrict US tax authorities from obtaining needed information'. The measures could end years of financial secrecy that have protected the super-rich and international businesses as they move money from one jurisdiction to another.

http://www.guardian.co.uk/business/2008/nov/09/barack-obama-tax-havens-crackdown

I do not know enough to have an informed opinion, but to me it seems fair that everyone should pay taxes, especially now that we are in such dire financial trouble.

What are the negatives of tax havens? Can anyone explain to me why it should be kept? I am asking this as about 7 million Americans are unemployed at this moment, and the numbers are growing. Will it be beneficial to our economy if he succeeds?