Passages from the chapter titled: Muslim World Traveller (emphasis by moi)
...Shortly after divorcing Obama Sr., Ann Dunham married an Indonesian Muslim, Lolo Soetoro Mangunharjo. She had met Soetoro, just she had met Obama Sr., when both were students at the University of Hawaii. At some point, Soetoro almost certainly adopted Dunham's son, who became known as "Barry Soetoro." Obama's lengthy, deeply introspective autobiography does not adddress whether he was adopted by the stepfather whose surname he shared for many years, but in all likelihood that did happen in Hawaii, before the family moved to Jakarta.
Under Indonesian law, adoption before the age of six by an Indonesian male qualified a child for citizenship. According to Dreams from my Father, Obama was four when he met Solo Soetoro. His mother married Soetoro shortly thereafter. Obama was already registered for school when he and his mother relocated to Jakarta, where Soetoro was an oil-company executive and liaison to the Indonesian government. That was in 1966, when Obama was five. Obama attended Indonesian elementary schools, which, in Suharto's police state, were generally reserved for citizens (and students were required to carry identity cards that matched student registration information). The records of the Catholic school Obama Soetoro attended for three years identify him as a citizen of Indonesia.
Given the president's adamant refusal to address issues related to his birth and citizenship, it is fair to infer that Obama obtained Indonesian citizenship through his adoption by Soetoro in Hawaii. That inference is bolstered by the 1980 divorce submission of Ann Dunham and Lolo Soetoro, filed in Hawaii state court. It said "the patries" (Ann and Lolo) had a child (name not given) who was no longer a minor (Obama was 19 at the time). If Soetoro had not adopted Obama, there would have been no basis for the couple to refer to Obama as their child - he'd have been only Ann Dunham's child.
....Of all places, why would Obama travel to Pakistan at that time? And how did he enter the country? Did he use an American passport to enter a police state in which it was dangerous for Americans? Or did he have travel documents from another country -which would raise the question also posed by his Indonesian years: Was Obama a citizen of an Islamic country? Those questions weren't pursued. Apparently the press didn't find anything newsworthy about the college friends involved in Obma's trip. Mohammed Hassan Chandoo, for example, became a New York financial consultant and a major Obama fundraiser. His brother, Mohammed Askari Chandoo, reportedly ran a crudely anti-Bush website and, besides raising money for Obama's successful 2004 Senate campaign, also organized voter registrations drives in mosques.
Nor was there media interest in the most intriguing (known) aspect of the trip: Obama stayed for part of it in the Jacobabad home of one of Pakistan's most prominent political families. He was hosted by the Soomros, members of the Pakistan Muslim League (a political party that is now split into several factions). Obama's host, Ahmad Mian Soomro, was a longtime Pakistani parliamentarian. His son, Muhammad Mian Soomro, who is about ten years older than Obma, not only became a very successful international banker; he was also chairman of the Pakistani Senate, became a caretaker prime minister in 2007, and served as the country's interim president when Pervez Musharraf was ousted in 2008 - holding the office for a month, until the election of Benazir Bhutto's widower, Asif Ali Zardari.
Nothing very interesting about that, right? Just move along.