France dwarfs United States: about 635,064 km² km² against 9,439,424 km² km². At true size France is about 14.9× larger — the whole of United States fits into France roughly 14 times.
France sits in Europe, United States in North America. On the old Mercator map the latitude gap distorted how large each felt beside the other; at true size the answer is simply 14.9×.
The old Mercator map treated both about equally (1.9× vs 2× inflation), so at least their relative sizes were preserved — even if both were drawn at the wrong absolute scale.
France fits 14× into United States.