For more than fifty years, North American Aerospace Defense Command (NORAD) has been responsible for conducting aerospace warning and control missions for the defense of North America. In accomplishing those operations, Commander NORAD is responsible for making the official warning to both the president of the United States and the prime minister of Canada if North America is suddenly under aerospace attack.

By Randall DeGering

How can a pandemic like SARS be halted in the modern age of air travel? This article argues that the classical mathematical models of epidemics are inadequate for describing the impact of air travel on the spread of contagions like SARS.

By Ted G. Lewis