The fifteen departments and their portfolios
The US Cabinet comprises 15 executive departments whose secretaries advise the President and head their agencies. State manages foreign affairs; Defense oversees the military; Treasury handles finances and taxation; Justice enforces federal law. Interior, Commerce, Labor, Health and Human Services, Housing and Urban Development, Transportation, Energy, Education, Veterans Affairs, and Homeland Security complete the list. Each department has thousands to hundreds of thousands of employees and a budget in the billions.
Cabinet departments do not exist in a vacuum; Congress created them by statute, controls their budgets, and can modify or eliminate them. The President appoints secretaries subject to Senate confirmation, and those appointees are responsible both to the President and to the laws Congress passes. This creates tension: a President cannot simply order a department to violate federal law, and Congress can constrain a President's policy goals by restricting department budgets or authority.
Budget and headcount disparities
Department budgets vary dramatically. Defense spends over $800 billion; Health and Human Services (which administers Medicare and Medicaid) spends over $2 trillion, though much is transfer payments rather than agency operations. Treasury's budget is modest, but it collects federal revenue and manages the debt. Smaller departments like State or Education spend $10-30 billion annually but shape policy far beyond their budget impact.
Headcount similarly varies. Veterans Affairs employs nearly 400,000 people; Social Security Administration employs over 60,000; smaller departments like State employ around 10,000 foreign service and civil service staff. These numbers reflect mission complexity: defense and veterans affairs manage massive operations, while foreign affairs is more streamlined. Budget and staffing requests are annually contentious in Congress, reflecting competing priorities and ideological differences about government size.