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. Judicial power is exercised by the judicial branch (or judiciary), composed of the Supreme Court and lower federal courts. The judiciary's function is to interpret the United States Constitution as well as federal laws and regulations. This includes resolving disputes between the executive and legislative branches. The federal government of the United States was established by the Constitution. American politics has been dominated by two parties, the Democratic Party and the Republican Party, since the American Civil War, although other parties have also existed.
Major differences between the political system of the United States and that of most other developed democracies are the power of the Senate as the upper house of the legislature, the wide scope of power of the Supreme Court, the separation of powers between the legislature and the executive government, and the dominance of the two main parties – the United States being one of the world's developed democracies in which third parties have the least political influence.
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.
States governments have the power to make law on all subjects that are not granted to the national government or denied to the states in the U.S. Constitution. These include education, family law, contract law, and most crimes. Unlike the national government, which only has those powers granted to it in the Constitution, a state government has inherent powers allowing it to act unless limited by a provision of the state or national constitution.
Like the national government, state governments have three branches: executive, legislative, and judicial. The chief executive of a state is its popularly elected governor, who typically holds office for a four-year term (although in a few states the term is two years). Except for Nebraska, which has one-chamber legislature (known as a unicameral legislature), all states have a bicameral legislature, with the upper house usually called the Senate and the lower house called the House of Representatives, the House of Delegates, Assembly or something similar. In most states, senators serve four-year terms, and members of the lower house serve two-year terms.
The constitutions of the various states differ in some details but generally follow a pattern similar to that of the federal Constitution, including a statement of the rights of the people and a plan for organizing the government. State constitutions are generally more detailed, however.
About 28% of the people live in cities of 100,000 or more population. City governments are chartered by states, and their charters detail the objectives and powers of the municipal government. For most big cities, cooperation with both state and federal organizations is essential to meeting the needs of their residents.
Types of city governments vary widely across the nation. However, almost all have some kind of central council, elected by the voters, and an executive officer, assisted by various department heads, to manage the city's affairs.
There are three general types of city government: the mayor-council, the commission, and the council-manager. These are the pure forms; many cities have developed a combination of two or three of them.
Mayor-Council. This is the oldest form of city government in the United States and, until the beginning of the 20th century, was used by nearly all American cities. Its structure is similar to that of the state and national governments, with an elected mayor as chief of the executive branch and an elected council that represents the various neighborhoods forming the legislative branch. The mayor appoints heads of city departments and other officials, sometimes with the approval of the council. He or she has the power of veto over ordinances — the laws of the city — and frequently is responsible for preparing the city's budget. The council passes city ordinances, sets the tax rate on property, and apportions money among the various city departments. As cities have grown, council seats have usually come to represent more than a single neighborhood.
The Commission. This combines both the legislative and executive functions in one group of officials, usually three or more in number, elected city-wide. Each commissioner supervises the work of one or more city departments. One is named chairperson of the body and is often called the mayor, although his or her power is equivalent to that of the other commissioners.
Council-Manager. The city manager is a response to the increasing complexity of urban problems, which require management expertise not often possessed by elected public officials. The answer has been to entrust most of the executive powers, including law enforcement and provision of services, to a highly trained and experienced professional city manager.
The city manager plan has been adopted by a large number of cities. Under this plan, a small, elected council makes the city ordinances and sets policy, but hires a paid administrator, also called a city manager, to carry out its decisions. The manager draws up the city budget and supervises most of the departments. Usually, there is no set term; the manager serves as long as the council is satisfied with his or her work.
In most U.S. counties, one town or city is designated as the county seat, and this is where the government offices are located and where the board of commissioners or supervisors meets. In small counties, boards are chosen by the county as a whole; in the larger ones, supervisors represent separate districts or townships. The board collects taxes for state and local governments; borrows and appropriates money; fixes the salaries of county employees; supervises elections; builds and maintains highways and bridges; and administers national, state, and county welfare programs. In very small counties, the executive and legislative power may lie entirely with a sole commissioner, who is assisted by boards to supervise taxes and elections. In some New England states, counties do not have any governmental function and are simply a division of land.
The government is usually entrusted to an elected board or council, which may be known by a variety of names: town or village council, board of selectmen, board of supervisors, board of commissioners. The board may have a chairperson or president who functions as chief executive officer, or there may be an elected mayor. Governmental employees may include a clerk, treasurer, police and fire officers, and health and welfare officers.
One unique aspect of local government, found mostly in the New England region of the United States, is the town meeting. Once a year — sometimes more often if needed — the registered voters of the town meet in open session to elect officers, debate local issues, and pass laws for operating the government. As a body, they decide on road construction and repair, construction of public buildings and facilities, tax rates, and the town budget. The town meeting, which has existed for more than three centuries in some places, is often cited as the purest form of direct democracy, in which the governmental power is not delegated, but is exercised directly and regularly by all the people.
Voting rights are sometimes restricted as a result of felony conviction, but such laws vary widely by state. Election of the president is an indirect suffrage: Voters vote for electors to vote for President.
At the time of the United States' founding, the economy was predominantly one of agriculture and small private businesses, and state governments left welfare issues to private or local initiative. As in the UK and other industrialized countries, laissez-faire ideology was largely discredited during the Great Depression. Between the 1930s and 1970s fiscal policy was characterized by the Keynesian consensus, a time during which modern American liberalism dominated economic policy virtually unchallenged. Since the late 1970s and early 1980s, however, laissez-faire ideology has once more become a powerful force in American politics. While the American welfare state expanded more than threefold after WWII, it has been at 20% of GDP since the late 1970s. Today, modern American liberalism, and modern American conservatism are engaged in a continuous political battle, characterized by what the Economist describes as "greater divisiveness [and] close, but bitterly fought elections."
Prior to World War II the United States pursued a policy of isolationism in foreign affairs by not taking sides in conflicts between foreign powers. The country abandoned this policy when it became a superpower, but the country remains skeptical of internationalism. The ideology of the incumbent President and the President's advisers largely determines the government's attitude in foreign affairs.
Each of these five parties shares a degree of national attention by attaining the mathematical possibility of its nominee becoming President of the United States—i.e., having ballot status for its presidential candidate in states whose collective total is at least half of the Electoral-College votes—in either the most recent presidential election, in 2004, or the next one, in 2008.
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 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, but such participation does not restrict one's choices in any way; nor does it give a person any particular rights or obligations with respect to the party, other than possibly allowing that person to vote in that party's primary elections (elections that determine who the candidate of the party will be). 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, affiliated organizations, and other individuals important to the party. However, the national committees do not have the power to direct the activities of individual members of the party.
When a party controls the White House, the President is party leader and controls the national committee. Otherwise the leadership is diffuse.
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.
One type of private interest group that has grown in number and influence in recent years is the political action committee or PAC. These are independent groups, organized around a single issue or set of issues, that contribute money to political campaigns for U.S. Congress or the presidency. PACs are limited in the amounts they can contribute directly to candidates in federal elections. There are no restrictions, however, on the amounts PACs can spend independently to advocate a point of view or to urge the election of candidates to office. PACs today number in the thousands.
"The number of interest groups has mushroomed, with more and more of them operating offices in Washington, D.C., and representing themselves directly to Congress and federal agencies," says Michael Schudson in his 1998 book The Good Citizen: A History of American Civic Life. "Many organizations that keep an eye on Washington seek financial and moral support from ordinary citizens. Since many of them focus on a narrow set of concerns or even on a single issue, and often a single issue of enormous emotional weight, they compete with the parties for citizens' dollars, time, and passion."
The amount of money spent by these special interests continues to grow, as campaigns become more and more expensive. Many Americans have the feeling that these wealthy interests — whether corporations or unions or PACs organized to promote a particular point of view — are so powerful that ordinary citizens can do little to counteract their influences.
Many of America's Founding Fathers hated the thought of political parties. They were sure quarreling factions would be more interested in contending with each other than in working for the common good. They wanted individual citizens to vote for individual candidates, without the interference of organized groups — but this was not to be.
By the 1790s, different views of the new country's proper course had already developed, and those who held these opposing views tried to win support for their cause by banding together. The followers of Alexander Hamilton, the Hamiltonian faction, took up the name "Federalist"; they favored a strong central government that would support the interests of commerce and industry. The followers of Thomas Jefferson, the Jeffersonians and then the "Anti-Federalists," took up the name "Democratic-Republicans" they preferred a decentralized agrarian republic in which the federal government had limited power. By 1828, the Federalists had disappeared as an organization, replaced by the Whigs, brought to life in opposition to the election that year of President Andrew Jackson. Jackson's presidency split the Democratic-Republican party: Jacksonians became the Democratic Party and those following the leadership of John Quincy Adams became the "National Republicans." The two-party system, still in existence today, was born. (Note: The National Republicans of John Quincy Adams is not the same party as today's Republican Party.)
In the 1850s, the issue of slavery took center stage, with disagreement in particular over the question of whether or not slavery should be permitted in the country's new territories in the West. The Whig Party straddled the issue and sank to its death after the overwhelming electoral defeat by Franklin Pierce in Presidential Election of 1852. Ex Whigs often joined the new Know Nothing Party or the Republican Party. While the Know Nothing party was short lived, it was the Republicans that would survive the intense politics leading up to the Civil War. The primary Republican policy was that slavery be excluded from all the territories. Just six years later, this new party captured the presidency when Abraham Lincoln won the election of 1860. By then, parties were well established as the country's dominant political organizations, and party allegiance had become an important part of most people's consciousness. Party loyalty was passed from fathers to sons, and party activities — including spectacular campaign events, complete with uniformed marching groups and torchlight parades — were a part of the social life of many communities.
By the 1920s, however, this boisterous folksiness had diminished. Municipal reforms, civil service reform, corrupt practices acts, and presidential primaries to replace the power of politicians at national conventions had all helped to clean up politics.
Most officials in America are elected from single-member districts and win office by beating out their opponents in a system for determining winners called first-past-the-post—the one who gets the plurality wins, (which is not the same thing as actually getting a majority of votes). This encourages the two-party system; see Duverger's law.
Another critical factor has been ballot access law. Originally voters went to the polls and publicly stated which candidate they supported. Later on, this developed into a process whereby each political party would create its own ballot and thus the voter would put the party's ballot into the voting box. In the late nineteenth century, states began to adopt the Australian Secret Ballot Method, and it eventually became the national standard. The secret ballot method ensured that the privacy of voters would be protected (hence government jobs could no longer be awarded to loyal voters) and each state would be responsible for creating one official ballot. The fact that state legislatures were dominated by Democrats and Republicans provided these parties an opportunity to pass discriminatory laws against minor political parties, yet such laws did not start to arise until the first Red Scare that hit America after World War I. State legislatures began to enact tough laws that made it harder for minor political parties to run candidates for office by requiring a high number of petition signatures from citizens and decreasing the length of time that such a petition could legally be circulated.
Another factor is the parliamentary system. Third parties thrive under the parliamentary system in which governing coalitions are formed after elections. The United States is not a parliamentary system, and indeed, in the United States, it could be said that coalitions are formed before elections under the umbrella of party organizations.
It should also be noted that while the overwhelming majority of elected officials do identify with a political party, the political parties of the United States are much more individualistic than in other political systems (i.e. in a parliamentary system). More often than not, party members will "toe the line" and support their party's policies, but it is important to note that they are free to vote against their own party and vote with the opposition ("cross the aisle") if a particular policy is counter to the priorities and interests of their constituents. Recent examples of this can be seen in such highly controversial matters as Social Security reform, the federal budget, and some environmental policies.
"In America the same political labels—Democratic and Republican—cover virtually all public officeholders, and therefore most voters are everywhere mobilized in the name of these two parties," says Nelson W. Polsby, professor of political science, in the book New Federalist Papers: Essays in Defense of the Constitution. "Yet Democrats and Republicans are not everywhere the same. Variations—sometimes subtle, sometimes blatant—in the 50 political cultures of the states yield considerable differences overall in what it means to be, or to vote, Democratic or Republican. These differences suggest that one may be justified in referring to the American two-party system as masking something more like a hundred-party system."
This changed a great deal with the presidency of Franklin D. Roosevelt, whose New Deal included the founding of Social Security as well as a variety of other federal services and public works projects. Roosevelt's arguable success in the twin crises of the Depression and World War II led to a sort of polarization in national politics, centered around him; this combined with his increasingly liberal policies to turn FDR's Democrats to the left and the Republican Party further rightward.
During the 1950s and the early 1960s both parties essentially expressed a more centrist approach to politics on the national level and had their liberal, moderate, and conservative wings equally influential within both parties.
From the early 1960s, the conservative wing became more dominant in the Republican Party, and the liberal wing became more dominant in the Democratic Party. The 1964 presidential election heralded the rise of the conservative wing among Republicans. The liberal and conservative wings within the Democratic Party were competitive until 1972, when George McGovern's candidacy marked the triumph of the liberal wing. This similarly happened in the Republican Party with the candidacy and later landslide election of Ronald Reagan in 1980, which marked the triumph of the conservative wing.
By the 1980 election, each major party had largely become identified by its dominant political orientation. Although strong showings in the 1990s by reformist independent Ross Perot pushed the major parties to put forth more centrist presidential candidates like Bill Clinton and Bob Dole, polarization in the congress was cemented by the Republican takeover of 1994.
Liberals within the Republican Party and conservatives within the Democratic Party and the Democratic Leadership Council neoliberals have typically fulfilled the roles of so-called political mavericks, radical centrists, or brokers of compromise between the two major parties. They have also helped their respective parties gain in certain regions that might not ordinarily elect a member of that party; the Republican Party has used this approach with centrist Republicans such as Rudy Giuliani, George Pataki, Richard Riordan and Arnold Schwarzenegger. The 2006 elections sent many centrist or conservative Democrats to state and federal legislatures including several, notably in Kansas and Montana, who switched parties.