Enlistment into any branch of the U.S. military by citizens of countries other than the United States is limited to those foreign nationals who are legally residing in the United States and possess an Immigration and Naturalization Service Alien Registration Card (INS Form I-151/551 — commonly known as a “Green Card”)*. Applicants must be between 17 and 35; meet the mental, moral, and physical standards for enlistment; and must speak, read and write English fluently.
* The U.S. military branches cannot assist foreign nationals in obtaining admittance into the United States. Only after immigration procedures are completed and an applicant is legally residing in the United States may an application for enlistment be accepted.
The U.S. government agency responsible for immigration and naturalization is the U.S. Citizenship and Immigration Service. Their web site is at http://uscis.gov/graphics/index.htm