Just so you know it is pretty hard to lose your U.S. citizenship.   There are two ways.  The first is “expatriation”.   That is when you do something that causes you to lose your U.S. citizenship.   Almost always, it requires an intent on your part to give up your U.S. citizenship —- for most of us, it is very hard to give up your US citizenship by mistake.

The other option is denaturalization.   Denaturalization occurs if the government decides that you were improperly granted citizenship.    This occurs, for example, with the Nazi prison camp guards who lied when they entered the US and lied when they became US citizens.   If the USCIS finds out that a person lied when they entered the US or when they became a US citizen, the government can go back and decide that they improperly granted citizenship to that person at that time.  You can not be denaturalized for something that you did after you became a US citizen — it is basically for people who hid a disqualifying fact when they first came to the US (and obtained a green card) or when they became a citizen.   The relevance of lying when a person obtains a green card is that if he was not entitled to a green card, then he could not have been entitled to citizenship because a person has to get a green card before he can get citizenship.

Now back to expatriation.   In general, you have to specifically intend to give up your US citizenship in order to lose your US citizenship.    When a person becomes a US citizen, they need to say that they give allegiance only to the US and renounce all other citizenships.   The US courts have said that that really means nothing — a person who becomes a US citizen does not give up his other citizenships unless the other country requires it.   Likewise, a US citizen who marries a foreigner and goes to live in the other country and becomes a citizen there does not lose his US citizenship even if he takes an oath stating that he gives up his US citizenship — as long as he wants to keep his US citizenship.   But, if a person takes that oath and really wants to give up his US citizenship, he will be held to have lost his US citizenship.    In general, in order to give up your US citizenship, you need to go into a US consulate and sign a paper stating that you “really, really, really want to give up your US citizenship” (actually that is not a direct quote from the form).

There are, however, some other ways that you can give up your US citizenship without necessarily intending to.   An obvious one is if you join a foreign army and fight against the US.   If you join a foreign army in peace time and serve as an officer without first getting permission from the US, you could lose your citizenship.   If you become a citizen of a foreign state and you serve in a policy-making position in the government, you could lose your US citizenship.  I have known of at least two US citizens who went to foreign countries and became President or Prime minister — such people most likely lost their citizenship.  This is not a broad category.  Being a mailman or a policeman or a dog catcher or the town clerk will not cause you to lose your citizenship.    But holding most elected positions, especially on a national level (but maybe on state or local level) could cause you to lose your US citizenship.

Treason and armed rebellion against the US can also cause you to lose your US citizenship, but only if you intended to give it up.  Some people commit treason simply for monetary gain and not to overthrow the government — they are subject to criminal punishment for treason, but they do not lose their citizenship.   Other people commit treason in order to cause the defeat of the U.S.  Such people would be subject to losing their citizenship.

So, in summary, most people, doing what most people do in their day-to-day lives will not lose their US citizenship.   But be careful if you go to another country and serve in their military or become a citizen there and run for a governmental office.

I hope this is interesting and helpful.   Remember that this is not legal advice.  It is just a summary of certain aspects of immigration law which may or may not apply to your situation.   I encourage you to consult an attorney if you think any of this may apply to your situation.

Gunnar Armstrong