> > As always, make certain to always enter the US on your US passport
> > afterwards; otherwise, this can be considered a renunciation of choice.
>
> You mean one has the choice of using either passport but isn't allowed
> to choose which one to use when entering the US? That seems very odd to me.

While US law has no prohibition on US citizens having other
citizenships (or the passports that they are entitled to hold because
of those citizenships), US law does require that if a person holds US
citizenship, he must enter the US on a US passport.  Australia has a
similar policy.  Australians can possess dual citizenship, but they
must enter Australia on an Australian passport, even if they also hold
another passport.