Australian citizenship is a privilege that offers enormous rewards. By becoming an Australian citizen, you are joining a unique national community. Our country has been built on the combined contributions of our Indigenous people and those who came later from all over the world. We celebrate this diversity and at the same time, strive for a unified and harmonious nation.
How compelling are these arguments? The answer is "it depends." From the individual's perspective there are other considerations. Please note that the following represent what I was able to come up with as an American migrant in France. You may have others or you may disagree with my list. Also, these are reasons to become a citizen and not reasons to relocate and become a legal resident. A migrant moving to a country for personal or economic reasons or one who is escaping persecution or discrimination in his home country can live in the host nation's territory, have access to the job market and participate in most (if not all) social programs quite nicely as a "legal resident alien."
Integration: I call this "feeling at home." You speak the language, work, have friends and family who you love and you're happy to be living here, in this place, with these people.
Gratitude/Shame: the feeling that you have been granted opportunities to build a life in that country and having enjoyed most of the benefits of residency for so long, you now feel that it is important to make a commitment to that country. When asked why he became an American citizen, Christopher Hitchens said, "I realized that I've been living here a long time and that this country, this society, had been pretty welcoming to me. I was just cruising along with a green card and felt like I was cheating on my dues."
Permanent right to reside: under international law, your country of citizenship must allow you to leave and to return. Legal residents have no such rights (or these rights are limited) and can be deported.
Political equality: a desire to participate in the political process, to vote or run for office. As a citizen you are no longer "taxed without representation."
The Right to Live and Work in Multiple Countries/Territories: UK citizenship gives you the right to live and work in France and all the other countries of the EU. U.S. citizenship gives you the right to live and work in 50 states. Canadians, Mexicans and Americans may have an easier time getting the right to work or reside in other each others countries because of NAFTA.
Career opportunities: you want to be able to work in certain fields or industries that are closed to non-citizens: civil service, defense industry, and state-owned companies.
Family: as a citizen you can pass your citizenship to your children. You can also bring other members of your extended family to live with you.
Discrimination: you do not like the way some citizens teat you as an immigrant. You think you will be treated better (or at least have more protection) if you become a citizen.
The Quality of the Welcome: you feel that your destination country and its citizens are happy to have you here. You are actively encouraged to become a citizen because the people around you feel that you would be a great addition to the nation.
Citizenship is Something Special: the people around you are proud to be citizens of that country. They feel it is an honor and a privilege to have been born a citizen of (or naturalized in) country X.
Some reasons not to become a citizen:
The Rights of a Citizen in that country do not interest you: you are not interested in voting or running for office, you do not intend to reside permanently in that country, you are not planning to bring over your family, you have no desire to work in the defense industry or to become a "fonctionnaire."
The Duties of a Citizen are Unacceptable to you: military service in that country, for example, or taxation. The U.S. taxes ALL its citizens whether or not they are living in the U.S.
Loss of Other Citizenship: you will lose or put at risk the citizenship of your country of origin and you will deprive your children of the right to be born citizens of the country of their grand-parents.
Loss of Protection: Citizens have the right to ask for the aid and protection of their states of citizenship. In the case of dual nationals the principle of "dominant nationality" may be applied and you may not longer be able to ask for help of the country of which which you are a citizen but not a resident.
Political Ambitions: you would like, one day, to run for office in your home country or serve in a high position in the government. Even where it is allowed by law, you fear that you won't be selected or elected by your home country constituents if you have dual nationality.
Loss of property and inheritance rights: Apparently this used to be true of certain countries. It is still, theoretically, possible. Imagine you have an inheritance or property dispute in the home country. The sheer effort that will be required to defend your rights (not to mention the look on the judge's face when he/she find out that you live in and are now a citizen of another country) will be substantial which gives a distinct "home court advantage" to your adversaries.
Family Responsibilities: Some of my friends have aging or ill parents in the home country. If taking on another citizenship means that you cannot easily go home to care for them, that's a problem for you, for them and for the country they live in.
Social Pressure: The people of your home country may be genuinely offended that you are considering becoming the citizen of another country and they let you know it. Even where the law permits dual nationality, public feeling is against it.
Integration Seems impossible: You do not have the sense that the people around you like immigrants (resident or citizen) and they are either ambivalent or actively hostile to your presence. The political climate makes you uneasy. You feel that, no matter what you do, you will never be accepted by, and will always face discrimination from, the citizens of the host country.
Complicated Process: the process is long, bureaucratic and costly.
Citizenship is Nothing Special: the citizens of the receiving country do not seem proud of their country or of their citizenship. They don't see it as having value. When asked, they are unsure as to why you would bother.
In most debates about immigration, citizens tend to tout all the advantages of citizenship and ignore all the negative consequences. These people impute purely economic motivations to every immigrant or resident who is suspected of trying to take advantage of the host country in some way.
This is beyond ignorant. Just as no state can make citizenship laws in a vacuum, no individual makes a decision to ask for citizenship without doing some very deep thinking within his own particular context. Even where both countries accept dual nationality, the choice to ask for citizenship is a complicated moral, emotional, financial calculation where the individual must weigh all the factors for and against before making a decision.