December 13, 2002, the president of the United States announced that smallpox vaccination would be offered to some categories of civilians and administered to members of the military and government representatives in high-risk areas of the world. The events that precipitated that historic announcement included a series of terrorist attacks during the 1990s, which culminated in the catastrophic events of 2001.

Although preparedness for deliberate attacks with biologic weapons was already the subject of much public health planning, meetings, and publications as the twentieth century...