3 Politics of the United States

The United States is a federal constitutional republic, in which the President of the United States (the head of state and head of government), Congress, and judiciary share powers reserved to the national government, and the federal government shares sovereignty with the state governments.

The executive branch is headed by the President and is independent of the legislature. Legislative power is vested in the two chambers of Congress, the Senate and the House of Representatives. The judicial branch (or judiciary), composed of the Supreme Court and lower federal courts, exercises judicial power (or judiciary). The judiciary's function is to interpret the United States Constitution and federal laws and regulations. This includes resolving disputes between the executive and legislative branches. The federal government's layout is explained in the Constitution. Two political parties, the Democratic Party and the Republican Party, have dominated American politics since the American Civil War, although there are also smaller parties like the Libertarian Party, the Green Party, and the Constitution Party.

There are major differences between the political system of the United States and that of most other developed democracies. These include greater power in the upper house of the legislature, a wider scope of power held by the Supreme Court, the separation of powers between the legislature and the executive, and the dominance of only two main parties. Third parties have less political influence in the United States than in other developed country democracies.

The federal entity created by the U.S. Constitution is the dominant feature of the American governmental system. However, most people are also subject to a state government, and all are subject to various units of local government. The latter include counties, municipalities, and special districts.

This multiplicity of jurisdictions reflects the country's history. The federal government was created by the states, which as colonies were established separately and governed themselves independently of the others. Units of local government were created by the colonies to efficiently carry out various state functions. As the country expanded, it admitted new states modeled on the existing ones.

Organization of American political parties

American political parties are more loosely organized than those in other countries. The two major parties, in particular, have no formal organization at the national level that controls membership, activities, or policy positions, though some state affiliates do. Thus, for an American to say that he or she is a member of the Democratic or Republican party, is quite different from a Briton's stating that he or she is a member of the Conservative or Labour party. In the United States, one can often become a "member" of a party, merely by stating that fact. In some U.S. states, a voter can register as a member of one or another party and/or vote in the primary election for one or another party. Such participation does not restrict one's choices in any way. It also does not give a person any particular rights or obligations within the party, other than possibly allowing that person to vote in that party's primary elections. A person may choose to attend meetings of one local party committee one day and another party committee the next day. The sole factor that brings one "closer to the action" is the quantity and quality of participation in party activities and the ability to persuade others in attendance to give one responsibility.

Party identification becomes somewhat formalized when a person runs for partisan office. In most states, this means declaring oneself a candidate for the nomination of a particular party and intent to enter that party's primary election for an office. A party committee may choose to endorse one or another of those who is seeking the nomination, but in the end the choice is up to those who choose to vote in the primary, and it is often difficult to tell who is going to do the voting.

The result is that American political parties have weak central organizations and little central ideology, except by consensus. A party really cannot prevent a person who disagrees with the majority of positions of the party or actively works against the party's aims from claiming party membership, so long as the voters who choose to vote in the primary elections elect that person. Once in office, an elected official may change parties simply by declaring such intent.

At the federal level, each of the two major parties has a national committee (See, Democratic National Committee, Republican National Committee) that acts as the hub for much fund-raising and campaign activities, particularly in presidential campaigns. The exact composition of these committees is different for each party, but they are made up primarily of representatives from state parties and affiliated organizations, and others important to the party. However, the national committees do not have the power to direct the activities of members of the party.

Both parties also have separate campaign committees which work to elect candidates at a specific level. The most significant of these are the Hill committees, which work to elect candidates to each house of Congress.

State parties exist in all fifty states, though their structures differ according to state law, as well as party rules at both the national and the state level.

Despite these weak organizations, elections are still usually portrayed as national races between the political parties. In what is known as "presidential coattails", candidates in presidential elections become the de facto leader of their respective party, and thus usually bring out supporters who in turn then vote for his party's candidates for other offices. On the other hand, federal midterm elections (where only Congress and not the president is up for election) are usually regarded as a referendum on the sitting president's performance, with voters either voting in or out the president's party's candidates, which in turn helps the next session of Congress to either pass or block the president's agenda, respectively.