In U.S. immigration law, naturalization refers to the process of becoming a U.S. citizen rather than being born one. Permanent residents may apply for citizenship upon being a permanent resident for five years, or upon being a permanent resident for three years if they have been married to the same U.S. citizen spouse for at least three years. The requirements for persons who serve in the military are very different. Please see our Naturalization Through Military Service web page for more information.
The Bureau of U.S. Citizenship and Immigration Services (USCIS) is required to make a decision on a person's citizenship application within a reasonable period of time. If a person has had a citizenship interview, the law requires USCIS to make a decision within 120 days of the date of the interview. If USCIS denies a citizenship application, the citizenship applicant has the right to appeal the decision. To find out what you can do if USCIS delays or denies your citizenship application, please refer to our page on Delays and Denials of Citizenship Applications.
Lawful permanent resident status in the United States is not permanent. Under current U.S. immigration law, being convicted of certain crimes may make a permanent resident removable from the United States. In certain situations, this may be true even where the crime is a minor state law misdemeanor, or even if the crime occurred many years ago. Advantage of U.S. citizenship include not being removed from the United States for criminal convictions, the right to vote, the ability to travel or live freely outside the United States for long periods of time and return, the right to hold special government jobs, and eligibility for public benefits not available to non-citizens.
As Supreme Court Chief Justice Earl Warren wrote in his dissent in Perez v. Brownell (1948):
Citizenship is man's basic right for it is nothing less than the right to have rights. Remove this priceless possession and there remains a stateless person, disgraced and degraded in the eyes of his countrymen. He has no lawful claim to protection from any nation, and no nation may assert rights on his behalf. His very existence is at the sufference of the state within whose borders he happens to be. In this country the expatriate will presumably enjoy at most, only the limited rights and privileges of aliens and like the alien he might even be subject to deportation and thereby deprived of the right to assert any rights.