Here is a nice website for the guys who are against immigrant soldiers in the USA.

http://www.ailf.org/pubed/defendingamerica.htm

First sentence sums it up, they are speaking about the US Military: Our understanding of the meaning of American patriotism would not be complete without considering the pride and commitment immigrants demonstrate on behalf of the United States.

Might want to look around at some of the links and read up on immigration and the military. I'm sure some of those people would really appreciate your "thanks for you service, but I'm against you holding a weapon for USA".

Another good link about America revitalizaion and immigrants: http://www.ailf.org/pubed/pe_revitalize_index.asp

Presidents talking about immigration:
http://www.ailf.org/pubed/pe_presidents_index.asp