| Initialism | Year | Agency |
|---|---|---|
| DOJ | 1870 | Department of Justice |
| FBI | 1908 | Federal Bureau of Investigation |
| CIA | 1947 | Central Intelligence Agency |
| NSA | 1953 | National Security Agency |
| DIA | 1961 | Defense Intelligence Agency |
| ATF | 1972 | Bureau of Alcohol, Tobacco, Firearms and Explosives |
| DEA | 1973 | Drug Enforcement Administration |
| FEMA | 1979 | Federal Emergency Management Agency |
| TSA | 2001 | Transportation Security Administration |
| DHS | 2002 | Department of Homeland Security |
| ICE | 2003 | Immigration and Customs Enforcement |
