I was born in the United States and grew up in a French family. By French law, that makes me French. The only time that became a problem was when I was drafted. At age 18, I was one of the first to receive a permanent deferment due to the draft lottery. When I was drafted by France at age 21 (the age for those born outside France), I was told that if I was dodging the US draft America would not help me. On the other hand, service in American armed forces would satisfy my obligation to France.
The lottery deferment caused confusion since I was not called up, so the interviewer (an army colonel) stamped my form "Exempté" and told me to get out, since there was no regulation covering my case.
I have split my life between both countries and I believe my dual nationality and complete fluency in both languages have vastly enriched my life.