Precautionary vaccination in advance of an actual outbreak will vastly slow the spread of the infection, at the same time that it will mitigate the logistical nightmare of vaccinating millions of exposed individuals on short notice. "Ring vaccination" after the fact may have worked in countries where the principal mode of transportation is the donkey cart, but will be far less successful in our highly mobile society, unless the great majority are already immune.

Best of all, pre-vaccination of low-risk individuals would tend to discourage any enemy from using smallpox as a weapon against us in the first place.

Let's save one million of our 15 million doses for emergencies, and dilute the other 14 million 10-to-1 to pre-vaccinate 140 million low-risk Americans at once, giving top priority to those who have never been vaccinated, and then to those who have received only one vaccination. If 30% of these vaccinations don't "take," we'll still be way ahead of where we are now.