AUSA’s Institute of Land Warfare has released a new publication."Defending the Homeland: The Chemical Biological Radiological Nuclear Response Enterprise" (Torchbearer National Security Report, February 2014) discusses five unique organizational structures divided among federal and National Guard forces – each with a distinct role – that offer commanders scalable response options for chemical, biological, radiological or nuclear (CBRN) events.In a security environment destabilized by an ever-increasing number of actors who are determined to harm Americans in a myriad of ways, it is imperative for strategic landpower – Army, Marines and special operations forces – not only to deter and prevent attacks but also to develop and maintain the ability to manage the consequences of a large-scale attack or disaster within the nation’s borders.The Department of Defense (DoD) coordinates a wide range of Title 10 (federal) and Title 32 (National Guard) forces with dedicated capability to provide prompt and sustained assistance at domestic incident sites.The DoD CBRN Response Enterprise consists of five main structures.Fifty-seven weapons of mass destruction civil support teams (WMD-CSTs) – approximately one per state – each consist of 22 National Guard personnel who remain on standby 24 hours per day and act as CBRN event first responders.Seventeen National Guard CBRN enhanced response force packages (CERFPs), each comprising nearly 200 personnel, are distributed across the country and deployable within three to six hours of notification.Ten National Guard homeland response forces (HRFs) of battalion size bridge the capability gap between initial responders and follow-on Title 10 forces, forging operational links among other federal and civilian authorities.The Defense CBRN Response Force (DCRF) is the primary Title 10 response asset available if state authorities request federal assistance. Composed of 5,200 active and reserve component personnel and commanded by a two-star headquarters, the DCRF can mobilize within 24 to 48 hours.Two Title 10 command-and-control CBRN response elements (C2CREs) provide the headquarters, mission command and communications capacity necessary to rapidly generate a second or third DCRF if such a requirement were to emerge (for example, in the event of multiple near-simultaneous CBRN incidents).In the aftermath of a CBRN incident in the homeland, lives hang in the balance of (1) how rapidly help arrives, (2) what capabilities are immediately present at the scene and (3) how well the emergency responders can manage and adapt to the complexity of such an incident.Although major improvements have been made recently in developing the unique capabilities required for this mission, some challenges endure.Determining the ideal size and structure for the various response units is difficult; few metrics exist for establishing precisely how much capability would be required in a real CBRN environment.Integrated and collective training – focusing particularly on interoperability with civilian partners – must be a priority because of the geographical dispersion of response assets and the strict timelines required for CBRN response to be effective.If the nation ever does have to call upon its military to respond to a catastrophic domestic CBRN event, the expectations for its response forces will be immense.It is imperative that the forces comprising the CBRN Response Enterprise are properly structured, manned, trained and resourced to conduct their mission efficiently and effectively.This Torchbearer National Security Report may be read in its entirety at https://www.ausa.org/publications/defending-homeland-cbrn.This and other ILW publications are available online at http://www.ausa.org/ilw and can also be obtained by calling (800) 336-4570, ext. 4630, or by e-mailing a request to ilwpublications@ausa.org.