FATCA legislation is predicated on the faulty assumption that foreigners throughout the world with no predisposition to favor the U.S. will react positively to its attempts to convert them into unpaid IRS agents. Faced with similar investment and personnel options without the legal jeopardy and financial risks, reasonable people will choose non-U.S. alternatives. FATCA implementation will constitute a major disruption of the entire international financial world as we know it today. Reasonable persons and entities will develop effective antibodies to this perceived infection, in ways too numerous and manifold to predict. What can be predicted is that the cumulative effect of this legislation will be a major blow to U.S. economic interests and prestige. At stake for the United States is the potential loss of trillions of dollars of investment, the opportunity for American companies and financial institutions to compete in a competitive global environment and the possibility for American citizens residing overseas to survive and thrive. In brief, the economic future of the United States is at stake.

http://americansabroad.org/issues/fatca/fatca-bad-america-why-it-should-be-repealed/