My original citizenship country is Belgium. I was certain that, despite the efforts of the EU to harmonize their laws on this, Belgium did not allow double citizenship. However, it came to my attention a few days ago, that an American athlete, also competing for the US national team, and living from his skills in Belgium for the past years is being granted the Belgian nationality... Does that mean I would have to become an American citizen, lose my Belgian citizenship under Belgian law, and then re-apply, as an American this time, to get the Belgian nationality back (providing that the USA allows double nationality status)?
I don't think it is even that complex; suggest you look into this further, and consider consulting with a Belgian immigration attorney who has worked with other US-Naturalizers. It appears to be entirely possible:
Official Gov't site:
http://www.diplomatie.be/en/services/nationalitydetail.asp?TEXTID=42527
10. How can I lose my Belgian nationality?
You can lose your Belgian nationality if:
- you are at least 18 years old and you have voluntarily obtained another nationality
(as of 9 June 2007 : You will lose your Belgian nationality only in case the other nationality you voluntarily obtain is the nationality of one of the following countries : Austria, Denmark, France, Ireland, Italy, Luxemburg, the Netherlands, Norway, Spain, United Kingdom)
OR; (more)
(you can look for the US-based Belgian Consulate for similar info)
http://www.diplomatie.be/toronto/default.asp?ACT=5&content=32&id=34&mnu=34
Dual citizenship
Since the 9th of june 2007, Belgian nationals who acquire of their own free will the citizenship of a country non part of the Council of Europe Convention on the Reduction of Cases of Multiple Nationality and on Military Obligations in Cases of Multiple Nationality (May 6, 1963), keep their Belgian citizenship.
Belgian nationals who acquire of their own free will the citizenship of a country part of the aforesaid Convention, that is to say Austria, Denmark, Spain, France, Ireland, Italy, Luxemburg, Norway, The Netherlands and Great-Britain, still lose by right their Belgian citizenship.
http://en.wikipedia.org/wiki/Belgian_nationality_law
Loss of Belgian citizenship
You are at least 18 years old and you have voluntarily obtained another nationality (as of 9 June 2007 : You will lose your Belgian nationality only in case the other nationality you voluntarily obtain is the nationality of one of the following countries : Austria, Denmark, France, Ireland, Italy, Luxembourg, the Netherlands, Norway, Spain, United Kingdom)
It is also possible to lose Belgian citizenship in the following circumstances
Dual citizenship
There are some circumstances where it is possible to hold Belgian citizenship alongside another citizenship:
* As of June 9, 2007, a person acquiring another nationality will not lose Belgian nationality. The only exceptions to this rule are when the nationality acquired is that of one of the following nations: Austria, Denmark, France, Ireland, Italy, Luxembourg, the Netherlands
* "Belgian nationality? Official Belgium government website", AD, June 03, 2007
* (Dutch) "België voert dubbele nationaliteit in", AD, May 14, 2007
* Belgium Today, Vol. 12, Issue 1