How the U.S. government works
Last reviewed: April 25, 2026
The U.S. federal government is built on three independent branches that share, watch over, and limit each other. The framers of the 1787 Constitution were wary of concentrated power; the system they designed deliberately makes it slow to act unilaterally, and that is by design.
1. The three branches
Executive branch — the President
The President leads the executive branch and is both head of state and head of government. The role combines duties that are split between two figures in many parliamentary democracies. The President:
- Enforces federal laws and runs the federal administration (cabinet, agencies, embassies, military).
- Is commander-in-chief of the armed forces.
- Signs or vetoes bills passed by Congress.
- Nominates federal judges (including Supreme Court justices), ambassadors, cabinet secretaries, and senior agency officials — subject to Senate confirmation.
- Negotiates treaties (which the Senate ratifies).
- Serves a 4-year term and can be re-elected once (22nd Amendment, 1951).
Legislative branch — Congress
Congress is bicameral. Both chambers must agree for a federal law to pass.
- Senate: 100 senators, two per state regardless of population. Six-year terms, with one third up for election every two years. The Senate confirms presidential nominations and ratifies treaties.
- House of Representatives: 435 voting representatives, allocated by state population and re-apportioned every ten years after the census. Two-year terms — meaning the entire House is up for election every other year.
- Together, Congress writes federal statutes, sets the federal budget, and decides on taxes and tariffs.
- Congress can override a presidential veto with a two-thirds vote in each chamber.
- Congress can impeach the President, the Vice President, judges, and other federal officers (House charges; Senate tries).
Judicial branch — the courts
At the top sits the Supreme Court: nine justices nominated by the President and confirmed by the Senate, serving for life or until they retire or resign. Below it sit 13 federal Courts of Appeals (the "circuits") and 94 federal District Courts. The federal judiciary:
- Decides federal-law and constitutional cases.
- Can declare a law — federal or state — unconstitutional (judicial review, established in Marbury v. Madison, 1803).
- Resolves disputes between states, and certain disputes involving foreign parties.
Life tenure is the most striking feature for European observers: it gives Supreme Court appointments unusual political weight, since a single justice can shape constitutional doctrine for decades.
2. Checks and balances in practice
Each branch has tools to limit the others. Examples:
- The President can veto laws — Congress can override with two thirds of each chamber.
- The President nominates federal judges — the Senate confirms or rejects.
- The Supreme Court can strike down a law — but only when a real case reaches it; the Court does not issue advisory opinions.
- Congress can impeach and remove federal officials — the bar is high (two-thirds Senate conviction).
- Congress decides how to spend federal money — but the President signs the budget and can veto it.
The result is a slow, friction-heavy system. Important reforms typically need either rare bipartisan majorities, or the alignment of all three branches under one party's control.
3. Federalism: a second balance, vertical this time
On top of the horizontal split among branches, there is a vertical split between Washington and the 50 states. Approximate distribution:
- Federal: defense, foreign policy, currency, immigration, interstate commerce, customs, federal taxation, social security, federal antitrust.
- States: education, criminal law, family law, most healthcare regulation, state taxation, state-level voting rules, professional licensing.
- Concurrent (both): taxation, courts, roads, environmental regulation, public-health emergencies.
For more detail, see States vs federal government.
4. The Constitution
- Written in 1787, ratified in 1788, in force since 1789. The oldest written national constitution still in use.
- Supreme law of the land — every other law must be consistent with it.
- 27 amendments. The first ten (the Bill of Rights, 1791) protect free speech, religion, press, assembly, the right to bear arms, due process, and more.
- Hard to amend: two thirds of each chamber of Congress, then ratification by three quarters of the states.
5. The administrative state
Day-to-day federal action runs through executive-branch agencies: the Department of Justice, the Department of State, the Treasury, the Department of Defense, the IRS, USCIS, the EPA, the FDA, the FCC, and many more. These agencies issue regulations within authority delegated by Congress, prosecute violations, and administer programs. Federal courts can review their actions for legality and constitutionality.
6. Common European misreadings
- "The President can do X." Often no — many decisions need Congress, the Senate, or both. Executive orders are bounded by statute and the Constitution.
- "The Supreme Court is political." Justices have legal philosophies, but they react to cases, not policy agendas; not every controversial issue lands at the Court.
- "Washington decides for the country." Most rules touching daily life — schools, marriage, criminal sentencing, road rules — are written in state capitals.
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