Half of the Department of Energy is the nuclear-weapons enterprise.

Office of the Chief Financial Officer · DOE

The Department of Energy carries two budgets in one department. Most of it — budget function 050, national defense, the same function as the Department of War — is the National Nuclear Security Administration: the nuclear stockpile, the Navy's reactors, defense nonproliferation, and the Cold War weapons-complex cleanup. The rest is civilian: the Office of Science and the applied-energy programs. This monitor keeps the two strictly separate, reads the topline two ways — by budget function and by appropriation account — and reconciles both to the published department total to the dollar.