Thanks. I think the question is asking the opposite in terms of the transaction actually. The gift is nontangible property from a nonresident noncitizen (presumably hence originating in an offshore account) to someone with US status. In this case (nontangible property being given by a noncitizen nonresident) there is no gift tax. But in the other case (nontangible property being given by a US person to someone offshore) there would be potential gift tax liability.
The underlying rationale here I think is that a US persons money is potentially taxable in future by the IRS (i.e. gift tax, inheritance tax). So moving that money to a non-US sphere (by giving it to a nonresident noncitizen) is potentially liable for gift tax so you don't excape tax entirely. However moving money from a nontaxable sphere (held by a nonresident noncitizen) to a taxable sphere (giving it to a US person) makes it now taxable by the IRS in those other ways, so no taxable as a gift.
An alternate explanation is that gift tax is levied on the giver, not the recipient. So it is impractical to tax a non-resident noncitizen as the giver, whereas this is not the case if the giver is a US person.
