So he did. One of those Pakistani friends, Beenu Mahmood, saw a major change in Obama. Mahmood calls Obama "the most deliberate person I ever met in terms of constructing his own identity," according to Maraniss. The time after college, Mahmood says, "was an important period for him, first the shift from not international but American, number one, and then not white, but black."
Mahmood, Maraniss writes, "could see Obama slowly but carefully distancing himself as a necessary step in establishing his political identity as an American."
Years later, the picture of Obama as a young adult wondering whether or not he was really an American was precisely the image that the Hillary Clinton campaign wanted to impose on the middle-aged Obama. In internal memos, top Clinton strategist Mark Penn questioned Obama's "lack of American roots," writing that "Obama's roots to basic American values and culture are at best limited. I cannot imagine America electing a president during a time of war who is not at his center fundamentally American in his thinking and in his values."
Clinton didn't come out and say that during the campaign, but she did everything she could to present herself as the all-American candidate in the race. Her campaign didn't play Tom Petty's "American Girl" at all her rallies for nothing.
In the general election, the contrast between Obama and John McCain was, of course, even more stark. At the age Obama was wondering whether he was an American, McCain, the son and grandson of U.S. Navy admirals, was a newly commissioned officer at Naval Air Station Pensacola, headed for a noteworthy military career. It seems unlikely McCain spent much time musing on whether he was an American.
In the end, as the Maraniss excerpt has it, Obama chose to become an American in part because that's what he needed to be to accomplish his goals. The story of what he did after that momentous decision will, unfortunately, have to wait for another biography.