A permanent resident is not required to become a citizen and may reside in the United States indefinitely as a permanent resident. A permanent resident may want to obtain citizenship in order to gain the particular benefits citizenship conveys. A citizen can vote in national, state, and local elections within the U.S., but a permanent resident cannot. A naturalized citizen also gains the ability to run for office and hold a federal job. As a U.S. citizen, one can exit and enter the U.S. without any regard for the duration of absence, as opposed to a permanent resident who must be careful not to abandon his status by leaving the U.S. for an extended period of time. Finally, a U.S. citizen can petition for the admission of alien relatives to the U.S. that cannot be petitioned by a permanent resident.
(Updated 10/08/12 by NT)
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