I've been thinking a lot about citizenship recently both because of Serbia's political debate about new citizenship laws, and also because many B92 readers have emailed me letters (thank you!) often mentioning they themselves are citizens of multiple countries. Many members of my extended family including my Father, also have multiple citizenships. I'm not qualified to comment on political debate, but I can extend three practical considerations:
#1. Useful papers vs heartfelt allegiance
I've noticed as people start collecting citizenships, the importance and meaning of each citizenship often lessens in their hearts. A citizenship which in essence should mean what country you consider yourself to be on the "team" of (sort of like basketball teams, only in this case countries), instead becomes a matter of convenience. A matter of useful papers. For example, my Father uses his Irish citizenship pretty much soley for the purpose of getting in shorter, quicker lines in European airports when he has to go through passport control. Otherwise he considers himself American.
In fact I often hear Serbs refer to their various citizenships (Croatian, German, American, Australian, whatever you have) as "Passports" or "papers" as though that is all citizenship really is: useful travel documents. And, for Serbs in particular, external passports have been so useful in the past 15 years that it's understandable that they would think of passports as a primary extra-citizenship motivation.
It seems very odd to me though, but then I come from a country where only 27% of citizens even bother to get passports (and that number was just 7% two years ago before new laws requiring Americans carry passports for trips to Canada, Mexico and the Carribean.)
Anyway, if the Serbian government is hoping to get truely heartfelt allegience (including of course greater tax income, "improved" demographic data, and military/public service on demand, which are the three government benefits of increased citizenship) then just handing out passports to citizens of other countries won't help them with any of those objectives.
The more passports a person has, in general, the less they are a citizen of anywhere, except the world in general.
#2. Increased paperwork
If you hate paperwork and administration, extra citizenships can be a big pain. One of your passports, or driving licenses, or town citizen cards, or some other paper is constantly being outdated. I have one friend who spent two months this year just going around filing in various countries trying to get everything updated... and still one document, that later turned out to be vital, slipped through the cracks.
#3. Tax considerations
As I said above, a MAJOR reason why countries want citizens is to tax them. The USA in particular is very big on this. Before you accept another citizenship ALWAYS research the tax implications. Wikipedia has a lot of pretty good information on this, although with Serbia's changing laws, who knows how taxes for citizens may change in the coming years?
BIG tip: If you are thinking about getting a US greencard or passport, or you are pregnant and think it's a good idea to have your baby in the USA so your child is an automatic US citizen, please research taxes beforehand!
The USA taxes ALL citizens and greencard holders regardless of where they live or where they earn their income. And taxes are pretty high compared to Serbia. I pay 42% of my earned income in Federal and State taxes, not including sales or property taxes. If I live in Serbia fulltime and enter the USA less than 31 days per year, then I still have to file documents quarterly and pay thousands of dollars in some US taxes, including taxes on US property and "unearned income" such as interest on bank deposits anywhere in the world.
If I decide to give up my US citizenship, I would still have to file for and pay US taxes for 10 years after that! (In addition, the US might not ever give me a visa to visit again.)
If you have a baby that is born in the US and so is an automatic US citizen, that child has to begin filing for US taxes when the child is old enough to have an income as well -- no matter where in the world the child lives or what the income is from. The US tracks these things increasingly, so now if your child grows up and applies for a US passport years later, the IRS (tax department) will immediately ask that now-adult child for back taxes and documentation for his or her entire life!
So, yes you can get a passport, but it can be expensive. And as computerization and national tax cooperation increases worldwide, it's increasingly hard to hide from the tax man in another country.
Still considering multiple citizenships? I know I am. Good luck and please let me know what your advice is.