I have a daughter who has dual French/American nationality and has always lived in the United States. Currently she has a French passport but not an American one. We need to go to France soon for family reasons and may not have enough time to get her an American passport. Can she travel to and from Paris on her French passport alone?

With French passport, it means she can enter France without getting a visa and she can stay as long as she wishes.

The problem is the return trip, if she does not have US passport, and she hands French passport to immigration Officer, she will be considered French not American.

She must get US passport.... there is express service if you don't have much time, just pay extra.