I used to believe that because i was jewish, i wasn't american. What could have contributed to this idea is the fact that i didn't know the national anthem.
A childhood belief about nationalities

others believed things like this
- I grew up Jewish. Until I was about 10, I believed that everyone who wasn't Jewish was Catholic.— Philm35
- Since Germans speak German, I thought Jewish people spoke Jewish.— Lori
- Living near Canada's border without cable, I didn't know I was American. — Romania
- i always wondered why people sent plums to the queen, in the anthem "send her victorias"— anon uk
- when was little i used to believe that if you won the grand national you would become prime ministerAnon
- I used to think my birthday was a national holiday and the whole world celebrated it— アノン