If you got the talent and an extremely good documentation about what you're going to write, you cant write on what you want, IMO. For example, Emilio Salgari was a most popular Italian writer, he wrote many books about Sandokan, a Malaysian hero having lots of adventures in the jungle, with pirates and tigers and stuff like that. He had not a single Malaysian blood tear and never moved from Turin. He got what every good author should have: an endless imagination and a real talent.
No need to say that being Italian American would be an extra-bonus ("la ciliegina sulla torta", we say---the cherry on top of the cake)
