For starters have a look at the following link:
The U.S. govt. has made strides in vaccine acquisition since that article was published. From the CDC Emergency Preparedness pages:
Currently, the United States has a big enough stockpile of smallpox vaccine to vaccinate everyone in the United States in the event of a smallpox emergency.
This is not especially comforting when you take into account that a large percentage of the population is ineligible for vaccine and given also (per the New Yorker article) that near-universal levels of vaccination are not necessarily proof against extensive outbreaks.
I'll feel more secure when (if) they develop an effective treatment.