Homeland security involves protecting the United States from hostile attack from human or natural causes and responding to and recovering from such attacks. A number of governmental agencies are responsible for protecting U.S. homeland security and responding to and recovering from assaults on the U.S. homeland. This also applies in other countries as well. Threats to homeland security can involve conventional, nuclear, terrorist, and asymmetric attacks on U.S. citizens. They can also involve attacks on U.S. computer networks and critical infrastructures such as utilities, communication systems, roads, bridges, and the spread of pandemic diseases such as influenza.
Useful Library of Congress subject headings to search for government books and reports on homeland security in the Purdue Libraries online catalog include:
Additional resources include: