This argument has the form:
The majority (of people, nations, etc.) believe p; therefore, p
In this case, the subjective state of large numbers of people,
not just a single person, is being used as evidence for the truth
of a proposition. But the argument is still subjective--and
still fallacious. We can see why, once again, by identifying the
implicit assumption: namely, that whatever the majority believes
to be true is true. Majority opinion is obviously not infallible.