In 1981,when Obama visited Pakistan, US passports were valid for entry (In fact, Pakistan was running a PR campaign to encourage US citizens to visit).
For example GOOGLE turns up this article by an American travel writer about a '81 vist:
http://www.nytimes.com/1981/06/14/travel/lahore-a-survivor-with-a-bittersweet-history.html
including visa information:
"Tourists can obtain a free, 30-day visa (necessary for Americans) at border crossings and airports."
Then he should have no problem producing his passport then.
Then he should have no problem producing his passport then.
Is there any evidence that 0bama had an American passport in 1981?