First, there is assimilation into the culture of the Bible Belt yahoos who govern Oklahoma: the culture that sends a fool to the Senate who claims global warming is a hoax; the culture that thinks allowing gay people to marry will raise the divorce rate among heterosexual couples; the culture that regrets the outcome of the War of Northern Aggression and denies the Tulsa race riots like Ahmadinejad denies the Holocaust. This is the missionary culture that finds virtue in ostentatious public prayer, Matthew 6:5-6 notwithstanding.
Second, there are Cherokees assimilated like me, and I know more of them than I can count without taking my shoes off. We leave the Nation in pursuit of an education or a career. We always say we intend to go back. Then we get a dose of realism and think maybe we will retire there, because it's always "home" in some sense.
Without a doubt, many of my fellow outlanders will have kittens when they read this because they think they are Indian by blood rather than by practice. Maybe so, just like British royals. Lots of peoples have taken the position that virtue is inherited rather than accomplished, so the idea cannot be dismissed out of hand.