What makes a novel "American"?

There is a debate going on at the house over what defines an American Fiction book and author. Help us settle it!

Here at our house, a spirited discussion has ensued over what makes a book qualifiy for this site (honey has some books he'd like to review or have me review, and I turned him down, sparking the debate). I started a poll, and now this blog, hoping to nail down the definition.

In my opinion, to qualifiy as American Fiction, the author must be native to America, have lived a good portion of their life in America, and publish at least a few books here in addition to any they may publish while abroad.

In his view, America is a true melting pot, and authors who have transplanted here to live and write should be included, even if they were born elsewhere.

What do you think? Can you help us settle the argument? Talk about it in discussions - what defines American Fiction for you?