United States government

According to United States Constitution the President may require the Opinion of the principal Officer in each of the executive Departments, upon any subject relating to the Duties of their respective Offices (Article Two, Section 2, Clause 1).

Before the War
Government branches mentioned Fallout games: Possible Cabinet positions:
 * War Department - mentioned in Maxson Log (Department of Defence - according to van Buren screenshot concerning HERMES armor and according to Fallout 3 "Faction Profile – the Brotherhood of Steel"),
 * Department of Energy (mentioned in Fallout Bible timeline), its seat was Pentagon,
 * department or departments responsible for war bonds and Unamerican Activities Force supervision (if latter one was government dependent organization).
 * Environmental Protection Agency.
 * Secretary of War,
 * Secretary of Energy,
 * Secretary of Treasure,
 * Administrator of the Environmental Protection Agency (cabinet level administration officer).

The Enclave
The Cabinet was addresse of the Project report from United States Chemical Corps and Power Plant Operations report from Atomic Energy Commision. Its seat was Executive Office on the oil rig.
 * The only known cabinet level administration officer in the Enclave was Vice-President (President of the Senate also), the first person in the presidential line of succession (declaring to be republican).
 * Secret Service (USSS) was present there also - before the War, because of Divergence, in Fallout world it could be overseen by Department of Treasure. It is not certain, if USSS was part of the Enclave armed forces however.
 * Atomic Energy Commision present, its exact status is unknown, but it reported to the Cabinet (Department of Energy not mentioned).

Very likely Cabinet present in the Enclave was minimally staffed (eg. the first American President appointed a Cabinet of four people).

The destruction of the Enclave erased all trace of President Dick Richardson from history. According to one of Fallout 2 endings eventually the survivors of the Enclave find a home in the ranks of NCR. In that case it can be said, that there didn't survive any the USA President succesor.

See also: USA, Enclave.