This article is from the FAQ, by with numerous contributions by others.
If you are a U.S. citizen, you will be able to,
o get green cards for your spouse and unmarried children without a
o get green cards for your parents, your married children, and your
brothers and sisters
o get a U.S. passport
o work for the U.S. government or in the other jobs that are closed to
Also, a citizen can't be deported or kept out of the U.S.