Joe Conason writes this week about how companies keep their corporate interests offshore - to evade paying their fair share of taxes:

According to the Government Accountability Office, nearly all of America's top 100 corporations maintain subsidiaries in countries identified as tax havens. As the GAO notes, there could be reasons other than avoiding the IRS to set up branches in places such as Singapore, Luxembourg and Switzerland, where taxes are light or nonexistent and keeping clients' illicit secrets is considered a matter of national pride.

But what reason other than evasion could there be for Goldman Sachs Group to set up three subsidiaries in Bermuda, five in Mauritius, and 15 in the Cayman Islands? Why did Countrywide Financial need two subsidiaries in Guernsey? Why did Wachovia need 18 subsidiaries in Bermuda, three in the British Virgin Islands, and 16 in the Caymans? Why did Lehman Brothers need 31 subsidiaries in the Caymans? What do Bank of America's 59 subsidiaries in the Caymans actually do? Why does Citigroup need 427 separate subsidiaries in tax havens, including 12 in the Channel Islands, 21 in Jersey, 91 in Luxembourg, 19 in Bermuda and 90 in the Caymans? What exactly is going on at Morgan Stanley's 19 subs in Jersey, 29 subs in Luxembourg, 14 subs in the Marshall Islands, and its amazing 158 subs in the Caymans? And speaking of AIG, why does it have 18 subs in tax-haven countries? (Don't expect to find out from Fox News Channel or the New York Post, because News Corp. has its own constellation of strange subsidiaries, including 33 in the Caymans alone.)

When the cost of these shenanigans was last estimated two years ago, the U.S. government's annual loss in revenue due to tax avoidance by major corporations and super-rich individuals was pegged at about $100 billion -- considerably more than a rounding error, even today. But of course that is only a rough assessment, as is the estimate of $12 trillion in untaxed assets hidden around the world. Nobody will know for certain until the books are opened and transparency is established.

[...] None of these tax havens could exist without the connivance or at least the cooperation of the world's most powerful governments, which remain dominated by financial industry lobbyists even now. The Organization for Economic Cooperation and Development has sought greater transparency from the tax havens for years, hearing promises from most and defiance from a few.

[...] Perhaps the UBS case indicates a change in that unwholesome trend and a renewed willingness on the part of American authorities to crack the tax havens -- which was not a priority, to put it mildly, of the Bush administration. As a senator, Barack Obama supported legislation to break open the secret financial regimes, by retaliating against countries and principalities that refuse to cooperate. Now Congress and the White House should pass such legislation and make breaking the tax havens a high priority in partnership with the European Union, the OECD and World Bank. They could start by threatening to outlaw transactions between American banks and financial institutions in any country that rejects new rules for transparency and reciprocal information.