Can U.S. citizens maintain dual citizenship with another country?
25151566#8
A person who is considered a citizen by more than one nation has "dual citizenship". It is possible for a United States citizen to have dual citizenship; this can be achieved in various ways, such as by birth in the United States to a parent who is a citizen of a foreign country (or in certain circumstances the foreign nationality may be transmitted even by a grandparent) by birth in another country to a parent(s) who is/are a United States citizen/s, or by having parents who are citizens of different countries. Anyone who becomes a naturalized U.S. citizen is required to renounce any prior "allegiance" to other countries during the naturalization ceremony; however, this renunciation of allegiance renunciation of citizenship to those countries.
Citizenship of the United States
25151566#4
U.S. law permits multiple citizenship. A citizen of another country naturalized as a U.S. citizen may retain their previous citizenship, though they must renounce allegiance to the other country. A U.S. citizen retains U.S. citizenship when becoming the citizen of another country, should that country's laws allow it. U.S. citizenship can be renounced by Americans who also hold another citizenship "via" a formal procedure at a U.S. Embassy, and it can also be restored.
Citizenship of the United States
993845#37
Although the U.S. government does not endorse dual citizenship as a matter of policy, it recognizes the existence of dual citizenship and completely tolerates the maintenance of multiple citizenship by U.S. citizens. In the past, claims of other countries on dual-national U.S. citizens sometimes placed them in situations where their obligations to one country were in conflict with the laws of the other. However, as fewer countries require military service and most base other obligations (such as the payment of taxes) on residence and not citizenship, these conflicts have become less frequent.
United States nationality law
17005341#14
In accordance with the Law on Romanian Citizenship of 1991, Romanian citizens currently have the right to hold dual citizenship. Romanian citizens who apply for dual citizenship are not required to establish their residency in Romania and, if accepted, are granted all the same rights as non-dual citizens. The Romanian policy on dual citizenship is irrelevant to other states policy. In order to successfully become a dual citizen of Romania, a person must also meet the requirements of dual citizenship in the other country. There have been cases in which applicants have successfully restored their Romanian citizenship and as a result, lost citizenship of another country. The Romanian state does not claim responsibility for the loss of citizenship to another state as a result of being granted dual citizenship by Romania.
Romanian nationality law
30876330#5
As a result, the theory of perpetual allegiance largely fell out of favor with governments during the late 19th century. With the consensus of the time being that dual citizenship would only lead to diplomatic problems, more governments began prohibiting it, and revoking the nationality of citizens holding another nationality. By the mid-20th century, dual nationality was largely prohibited worldwide, although there were exceptions. For example, a series of U.S. Supreme Court rulings permitted Americans born with citizenship in another country to keep it without losing their U.S. citizenship.
Multiple citizenship
25151566#10
Under certain circumstances there are relevant distinctions between dual citizens who hold a "substantial contact" with a country, for example by holding a passport or by residing in the country for a certain period of time, and those who do not. For example, under the Heroes Earnings Assistance and Relief Tax (HEART) Act of 2008, U.S. citizens in general are subject to an expatriation tax if they give up U.S. citizenship, but there are exceptions (specifically ) for those who are either under age 18½ upon giving up U.S. citizenship and have lived in the U.S. for less than ten years in their lives, or who are dual citizens by birth residing in their other country of citizenship at the time of giving up U.S. citizenship and have lived in the U.S. for less than ten out of the past fifteen years. Similarly, the United States considers holders of a foreign passport to have a substantial contact with the country that issued the passport, which may preclude security clearance.
Citizenship of the United States
54362192#38
Even countries which permit dual citizenship may bar dual citizens from government positions. Australia for example does not allow dual citizens to stand for election to Parliament, while Taiwan bars dual citizens from most public-sector positions. Diplomatic and consular positions present additional difficulties. The Vienna Convention on Diplomatic Relations and Vienna Convention on Consular Relations state that a country may refuse to receive a diplomat or consular officer who holds the citizenship of the receiving country. Based on this, the State Department does not receive U.S. citizens and non-citizen nationals as diplomats representing a foreign country to the United States. The State Department permits such individuals to represent a foreign country in its diplomatic mission at United Nations Headquarters in New York City, but while in such positions they enjoy only official acts immunity and not diplomatic immunity. Thus, an individual wishing to assume a diplomatic or consular position in the United States may choose to relinquish U.S. citizenship. One early example of this, which was described at the time as the first such case in U.S. diplomatic history, was Oskar R. Lange's decision to renounce citizenship in 1945 to become the Polish ambassador to the United States.
Relinquishment of United States nationality
54362192#37
Some foreign countries do not permit their citizens to hold other citizenships at all. Bars on dual citizenship take a variety of forms, but two common provisions in such countries' laws are that a foreigner seeking to become a citizen of the country generally must obtain release from any other citizenships according to the laws of those other countries (a provision seen for example in South Korea and Austria), and that a person who was born with dual citizenship must choose whether to retain the local citizenship or the foreign citizenship upon reaching the age of majority (e.g. in Japan). In the 1990s, many individuals relinquishing citizenship were naturalized citizens returning to their countries of birth; for example, the State Department indicated to the JCT that many of the 858 U.S. citizens who renounced in 1994 were former Korean Americans who returned to South Korea and resumed their citizenship there, which under South Korean nationality law required them to give up their U.S. citizenship. By the late 1990s, the number of relinquishments had fallen to about 400 per year. The State Department speculated that the 1997 Asian financial crisis resulted in "fewer people renounc[ing] their U.S. citizenship as a condition of employment in an Asian country".
Relinquishment of United States nationality
30876330#51
Multiple citizens who travel to a country that claims them as a citizen may be required to enter or leave the country on that country's passport. For example, a United States Department of State web page on dual nationality contains the information that most US citizens, including dual nationals, must use a US passport to enter and leave the United States. Under the terms of the South African Citizenship Act, it is an offence for someone aged at least 18 with South African citizenship and another citizenship to enter or depart the Republic of South Africa using the passport of another country. They may also be required, before leaving the country, to fulfill requirements ordinarily required of its resident citizens, including compulsory military service or exit permits.
Multiple citizenship
6271835#3
The United States, Canada, and Mexico all grant unconditional birthright citizenship and allow dual citizenship. The United States taxes its citizens and green card holders worldwide, even if they have never lived in the country. In Mexico, only naturalized citizens can lose their Mexican citizenship again (e.g., by naturalizing in another country).
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