Although the need for government to have leadership that provides direction is universal among states, the form that the government leadership assumes varies. Government structure varies significantly between the United States and Great Britain, despite that each is a democracy and share a common history.
In fact, the common history of the United States and Great Britain suggests reasons to explain the broad differences between the governments of each respective state. In the wake of the American Revolution, the people of the United States rejected the forms and institutions, most notably a monarchy and Parliament, of British government as well as British sovereignty. Possessing a democratic presidential government, the United States has two separately elected agencies of government. The executive and legislative branches of the United States, the President and Congress, respectively, both derive their power from the people, whereas in Great Britain only the legislative branch, Parliament, derives its power from the people, as the executive is elected by Members of Parliament, thus effectively combining both branches within a single institution.
The Parliamentary system in Great Britain and the Presidential system in the United States both have histories marked by an absence of abject failure, yet neither system can be considered truly perfect. Consequently, the analyst cannot conclude that either system is better; rather, he must recognize that there are merits and faults in both systems. The Parliamentary system tends to legislate efficiently, whereas a presidential system tends toward gridlock. However, the presidential system grants both elected representatives and citizens greater influence in government. The Parliamentary system tends to favor Prime Ministers who have much experience, whereas the Presidential system favors Presidents who are responsive to the general will of the people.
Also every week the British prime minister appears before the House of Commons and must answer questions put to him or her by the members of Parliament. Sometimes it is suggested that the president of the United States should be subject to similar questioning by members of Congress, as a way of encouraging closer interaction between president and Congress. If the president did so, however, it would be his or her choice; the president is elected directly by the people and is answerable to the voters rather than the legislature. Whereas the prime minister has no choice because he or she is a member of Parliament and is directly accountable to that body. Herein lies a very basic difference between the presidential system of government as it exists in the United States and the parliamentary system that has evolved in Great Britain.
Another point is that the framers of the U.S. Constitution adopted the principle first enunciated by the Baron de Montesquieu of separation of powers. They carefully spelled out the independence of the three branches of government: executive, legislative, and judicial. At the same time, however, they provided for a system in which some powers should be shared: Congress may pass laws, but the president can veto them; the president nominates certain public officials, but Congress must approve the appointments; and laws passed by Congress as well as executive actions are subject to judicial review. Thus the separation of powers is offset by what are sometimes called checks and balances.
In a parliamentary system, by contrast, the legislature holds supreme power. The prime minister is chosen by members of the legislature (Parliament) from among their own number and in practice is the leader of the majority party in the legislature. The cabinet members must also belong to the legislature, where they are subject to the same kind of questioning that the prime minister experiences. If the prime minister loses the support of the majority in the legislature on a significant vote, he or she must resign, and elections are called immediately. Thus, whereas in the United States, elections are held at fixed intervals, in Britain and other parliamentary countries, they may occur at any time, the only restriction being (in Britain) that they must be held at least once every five years.
In Conclusion, the governments of Great Britain and the United States of America have many differences, they are, at the core, provides leadership and direction to their nation.