Obama wrote a whole book about his quest for identity, called "Dreams From My Father," and in it he never directly deals with the reasons he reverted to his birth name, or the impression it made on his relatives. The book is a deeply personal narrative that takes some liberties with the facts for the sake of a coherent tale
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In writing the book he pulled the ultimate magician trick. Keeping everyone attention on his African roots and ignoring his American roots which made him extremely wealthy from about age 10 when his grandmother was made his guardian to manage the finances he inherited from her father.
He still is declaring income from the family trust. Check his schedule E