Because he used his Indonesian passport in 1981 to travel abroad to Pakistan. That is probably why he went to Indonesia before traveling on to Pakistan, to renew his passport. You see, in Indonesia only children less than 18 years can have dual citizenship, but they eventually must make a choice.
It seems Barack Obama made his in 1981 when he renewed his Indonesian passport as an Indonesian citizen.
You cannot have divided loyalties with another nation and be President.
yours is a good explanation
Is the US President required to hold only one nationality (legally), or it's a matter of politics: when people know he has two nationalities, they would less likely to vote for him?
If provable, that would be a knockout, down for the count.
Anyone who has that proof owns him.
Do we know which passport Obama used for that trip? He would have been 20, correct? If he used a passport from another country, would that automatically affect his loyalties toward America?
This would definitely be worth a court case, but probably not enough to disqualify him citizenship.
For instance, voting in another country is supposed to be a factor in determining country loyalty. However, there are many citizens of the USA who have voted in other countries (Mexico, Israel, etc.). I would actually think that using a passport conferred on you would be a similar semi-minor infraction, but if you had otherwise been a model citizen of the USA, I'd not think we would revoke citizenship for either a vote nor usage of another passport. (I certainly have heard of cases of Americans with dual citizenship choosing to travel to dangerous places using the local and not the American passport.)
I do not believe that asking for a passport renewal (as Obama may have done in 1981) is a citizenship disqualification either, because what you are doing is asking for an update of a document. Your citizenship of a country does not change whether or not you have a passport. Many Americans do not have a passport, and yet they are citizens in good standing.
The law looks at several of these "loyalty to another state" issues when it decides to revoke American citizenship. There has to be something egregious before a citizenship is revoked. Not even fighting in the army of another state is cause for automatic revocation of American status.
You make your statement as if you know it to be a hard fact. If it is please confirm it. If you are just engaged in more idle speculation please say so.