On February 28, 2003 President Bush signed Homeland Security Presidential Directive/HSPD-5 which details the governments response to "Domestic
Incidents"
Its purpose:
To enhance the ability of the United States to manage domestic incidents by establishing a single, comprehensive national incident management
system.
Its interesting that this is both a FEMA and Homeland Security document. I assume that its a division of labor. But it clearly spells out that HLS is
the lead agency and the Secretary of the department is the primary Federal official for domestic incident management.
To prevent, prepare for, respond to, and recover from terrorist attacks, major disasters, and other emergencies, the United States Government shall
establish a single, comprehensive approach to domestic incident management. The objective of the United States Government is to ensure that all levels
of government across the Nation have the capability to work efficiently and effectively together, using a national approach to domestic incident
management. In these efforts, with regard to domestic incidents, the United States Government treats crisis management and consequence management as a
single, integrated function, rather than as two separate functions.
This is a kind of catch all so pretty much any incident, terrorism or otherwise would fall under the HLS purview. From a major earthquake in
California, to hurricanes, to a biowarfare incident its all covered.
There are four conditions for the government to mobilize a response. If any one of the four are met, this directive is in force.
(1) a Federal department or agency acting under its own authority has requested the assistance of the Secretary; (2) the resources of State and local
authorities are overwhelmed and Federal assistance has been requested by the appropriate State and local authorities; (3) more than one Federal
department or agency has become substantially involved in responding to the incident; or (4) the Secretary has been directed to assume responsibility
for managing the domestic incident by the President.
In otherwords, its pretty easy for any disaster to meet the criteria. With the potential of an Avian influenza outbreak, it would require a Federal
effort to coordinate care rather than states, counties, or cities, trying to go it alone.
However, the directive also recognizes the rights of the state governments as well. But Federal "Interests" as outline below is pretty vague
The Federal Government recognizes the roles and responsibilities of State and local authorities in domestic incident management. Initial
responsibility for managing domestic incidents generally falls on State and local authorities. The Federal Government will assist State and local
authorities when their resources are overwhelmed, or when Federal interests are involved.
Before people go off an a FEMA rant, it is important to note that this type of preparation is exactly what we would expect to deal with a potential
threat or disaster. If we had an outbreak and the government was not prepared, we would be impeaching or indicting officials for failing to do so.
The document in its entirety can be found at
Homeland Security Presidential Directive/HSPD-5 
