Enlisted Marine Corps ranks are broken down into three levels, Junior Enlisted, Non-Commissioned Officers, and Staff Non-Commissioned Officers. As a Marine moves up the ladder his or her responsibility and contribution to the mission increases.
Also, children born abroad to two non-citizen nationals or to one alien parent and one non-citizen national parent are eligible for non-citizen national status. This is so rare that the State Department does not even issue a certificate for it. Non-citizen nationals are delineated as such in their passports.
Most U.S. nationals, including dual nationals, must use a U.S. passport to enter and leave the United States. Dual nationals may also be required by the foreign country to use its passport to enter and leave that country. Use of the foreign passport does not endanger U.S. nationality.