Why the big rush to licence the Monkeypox vaccine in 2019, when there was no Monkeypox outbreak?

Why the big rush to licence the Monkeypox vaccine in 2019, when there was no Monkeypox outbreak?

Dr. Meryl Nass: Monkeypox has never spread like this before; it started out simultaneously between 12 and 20 countries on four continents. I don’t know how one wave can cause so many countries to be infected at once with a disease that almost never spread person to person before?