"The Department of Homeland Security (DHS) was established by the Homeland Security Act of 2002 (P.L. 107-296, hereinafter the HSA) and became operational January 24, 2003, barely 16 months after the terrorist attacks on the Pentagon and World Trade Center on September 11, 2001. Rather than being as a completely new entity, the department was established by assembling existing parts of 22 different federal agencies and departments into a new framework. The timing and means of establishing DHS, coupled with the perceived urgency of its mission in its early years, hastened the growth and development of the department's operational capabilities. At the same time, these factors hindered potential efforts to more fully integrate the functions of the department's different components. […] In October 2006, DHS Secretary Michael Chertoff put forward a master plan for 'unifying … core headquarters facilities with those of our operating components,' which essentially broadened the Coast Guard project to include the overall DHS headquarters consolidation as well, moving 14,000 of the 22,000 people that staff headquarters functions for the department and its components to St. Elizabeths. Earlier that year, the White House issued a report entitled 'The Federal Response to Katrina: Lessons Learned.' While this report did not call for a consolidated DHS headquarters per se, it did state a need to develop a joint departmental operations center with robust command and control functions to promote more efficient incident response. This need would be used to help advocate for the consolidated headquarters project in future years. Since that year, Administrations of both parties have requested funding for this initiative to support a coordinated construction plan. However, this project has not received consistent funding--over 80% of the funding it has received so far came in FY2009 when a surge of supplemental funding combined with the regular appropriations for GSA [General Services Administration] and DHS provided almost $1.1 billion for the project."
CRS Report for Congress, R42753