[grumpygresh]

I would think that 0bama would cancel the passport of an American doing Christian humanitarian and/or missionary work abroad.

If a government does cancel a passport, does that mean that that person may not re-enter his home country? I would guess that in this instance that Australia would let him back in and prosecute him.

If such a person could not re-enter his home country, is there any responsibility for any government to take in a person in this circumstance?

[usurper]

If a government does cancel a passport, does that mean that that person may not re-enter his home country?

It means he can't get on a common carrier such as a plane or ship because they check passports before departure.

Since he can't walk to Australia he is basically banished.