International Issues
No, all ISBNs are international. They are merely assigned locally.
No. All ISBNs are international. There is no such thing as a US ISBN. ISBNs are international, but assigned locally.
No. All ISBNs are international. The only times a distributor or fulfillment house can assign an ISBN are a) if the product is sold by a publisher in a country that has no ISBN Agency or b) for internal tracking use only.