Though many people in Charleston may not realize it, you do not have to be an American citizen to be in the military. There have been many non-Americans who have served with the military for years, including during the Vietnam War. One of the benefits of serving during a "designated period of hostility" is that federal law allows for immigrants to waive their permanent residency requirements and naturalize as American citizens.
Even though this is the law, the military and the federal government have to go through very specific steps before someone is actually deemed an American citizen. If there is even the smallest mistake, however, it could mean that someone thinks he or she is a citizen, but actually isn't. This, of course, opens up individuals to the risk of deportation or even criminal charges.
Some of these noncitizens could go their whole lives without knowing they aren't citizens. Others, however, may find out the hard way when they apply for a passport or register to vote. Though the government may recognize that the mistake is not the individual's fault, they will likely require him or her to start accruing time as a permanent resident before allowing him or her to legally naturalize.
Citizenship and naturalization can be incredibly complex. Not only are there very strict requirements on who can become a citizen and the process of naturalization, but there are also a number of exceptions, too. If there is ever any question about whether an individual was granted citizenship, it is best to work closely with an immigration lawyer. For someone to find out he or she is not a citizen after being threatened with deportation is certainly not an ideal situation.
Source: Reuters, "Cuban-born man denied citizenship after almost 50 years in U.S.," Barbara Liston, May 13, 2014