The threat of nuclear attack is the highest it has been in a generation. While strategic nuclear weapons have historically been a primary focus of concern, smaller tactical nuclear weapons, and improvised nuclear devices (IND) have also emerged as threats of global concern. The damaging effects of nuclear weapons present unique challenges. These challenges are significantly different than those presented by conventional explosive threats, far beyond just the geographical extent of damage. This includes direct and higher order effects of nuclear device detonation resulting from factors such as airblast, drag loading, thermal radiation, prompt radiation, fallout deposition, fallout radiation, electromagnetic pulse (EMP), as well as critical interdependencies and cascading effects impacting a significantly broader area. While analytical evaluation methods and related technologies have vastly improved in these areas since the initial diminishment of the state-sponsored nuclear threat a generation ago, most of the existing empirical data and validation testing performed for nuclear explosive threats at large scale is many decades old at best. However, this legacy data still yields valuable insights into such extreme environments and can be a vital component of modern consequence evaluation.

This discussion will evaluate:

• Nuclear explosive threat types, deployment options, and objectives.
• The differences in damage mechanisms between nuclear and conventional explosive threats.
• Broader-scale consequences and how these may impact modern society in terms of damage effects, resilience, response, and recovery for such an event.

Due to the sensitive nature of this subject, only information available in the public domain will be discussed.