[Kansas58]

The United States does not recognize “dual citizenship” — and never has.
Your question is a moot point.

[rolling_stone]

the united states does recognize dual citizenship, pull your head out of your rear

...The U.S. Government recognizes that dual nationality exists but does not encourage it as a matter of policy because of the problems it may cause....

http://travel.state.gov/travel/cis_pa_tw/cis/cis_1753.html