United States nationality law

Article I, section 8, clause 4 of the United States Constitution expressly gives the United States Congress the power to establish a uniform rule of naturalization. The Immigration and Nationality Act of 1952 sets forth the legal requirements for the acquisition of, and divestiture from, American nationality. The requirements have become more explicit since the ratification of the Fourteenth Amendment to the Constitution, with the most recent changes to statutory law having been made by the United States Congress in 2001.

Adult citizens of the United States who are residents of one of the 50 states or the District of Columbia (Washington, D.C.) have the right to participate in the political system of the United States, as well as their state and local governments (with most states having restrictions on voting by persons convicted of felonies, and a federal constitutional prohibition on naturalized persons running for President and Vice President of the United States), to be represented and protected abroad by the United States (through U.S. embassies and consulates), and to live in the United States and certain territories without any immigration requirements. Felons can vote in over 40 states, and in at least 2 while incarcerated. Felons can also serve jury duty if approved.

Some U.S. citizens have the obligation to serve in a jury, if selected and legally qualified. Citizens are also required (under the provisions of the Internal Revenue Code) to pay taxes on their total income from all sources worldwide, including income earned abroad while living abroad. Under certain circumstances, however, U.S. citizens living and working abroad may be able to reduce or eliminate their U.S. federal income tax via the Foreign Earned Income Exclusion or the Foreign Tax Credit. U.S. taxes payable may be alternatively reduced by credits for foreign income taxes regardless of the length of stay abroad. The United States Government also insists that U.S. citizens travel into and out of the United States on a U.S. passport, regardless of any other nationality they may possess.

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