what type of government structure does the us have
Government Superficially, all governments have an official or ideal form. The United States is a constitutional republic, while the former Soviet Union was a socialist republic. However self-identification is not objective, and as Kopstein and Lichbach argue, defining regimes can be tricky.[14] For example, elections are a defining characteristic of an electoral democracy,[citation needed] but in practice elections in the former Soviet Union were not "free and fair" and took place in a one-party state. Voltaire argued that "the Holy Roman Empire is neither Holy, nor Roman, nor an Empire".[15] Many governments that officially call themselves a "democratic republic" are not democratic, nor a republic; they are usually a dictatorship de facto. Communist dictatorships have been especially prone to use this term. For example, the official name of North Vietnam was "The Democratic Republic of Vietnam". China uses a variant, "The People's Republic of China". Thus in many practical classifications it would not be considered democratic.
Government of Australia The Government of the Commonwealth of Australia (also referred to as the Australian Government, the Commonwealth Government, the Federal Government, and formally Her Majesty's Government) is the government of the Commonwealth of Australia, a federal parliamentary constitutional monarchy.
United States The United States is the world's oldest surviving federation. The federal republic  is a representative democracy, "in which majority rule is tempered by minority rights protected by law".[28] The United States is a founding member of the United Nations, World Bank, International Monetary Fund, Organization of American States (OAS), and other international organizations. The United States is a highly developed country, with the world's largest economy by nominal GDP and second-largest economy by PPP, accounting for approximately a quarter of global GDP.[29] The U.S. economy is largely post-industrial, characterized by the dominance of services and knowledge-based activities, although the manufacturing sector remains the second-largest in the world.[30] The United States is the world's largest importer and the second largest exporter of goods, by value.[31][32] Although its population is only 4.3% of the world total,[33] the U.S. holds 33% of the total wealth in the world, the largest share of global wealth concentrated in a single country.[34] The United States ranks among the highest nations in several measures of socioeconomic performance, including average wage,[35] human development, per capita GDP, and productivity per person.[36] The United States is the foremost military power in the world, making up a third of global military spending,[37] and is a leading political, cultural, and scientific force internationally.[38]
Politics of the United States There are a few 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 democratically run developed countries; this is because of a combination of stringent historic controls. These controls take shape in the form of state and federal laws, informal media prohibitions, and winner-take-all elections, and include ballot access issues and exclusive debate rules.