One of the many ways for people to obtain US green cards is through service in the American military. However, there are a number of conditions that one must meet if they are to obtain permanent resident status.
Individuals who wish to become permanent residents in the US must meet certain criteria: They must have enlisted in a branch of the US military outside of the country under any treaty or agreement that was in effect on October 1, 1991 and served 12 years if they have been honorably discharged from the service or served six years if they are on active duty and have re-enlisted for a total commitment of 12 years.
In addition, prospective citizens must be from a country that has an agreement with the US to allow its nationals to join the US military, which currently only include the Philippines, Micronesia and the Marshall Islands. Also they must receive a recommendation from the executive branch of the branch of the military in which they served.
If all of these criteria are met, applicants must file Form I-360, Petition for Amerasian, Widow(er) or Special Immigrant. If the applicant is living in America he must also file Form I-485, Application to Register Permanent Residence or Adjust Status.