US Politics

On the problems of the presidential system: http://scholar.harvard.edu/levitsky/files/1.1linz.pdf

By contrast, the only presidential democracy with a long history of constitutional continuity is the United States. The constitutions of Finland and France are hybrids rather than true presidential systems, and in the case of the French Fifth Republic, the jury is still out. Aside from the United States, only Chile has managed a century and a half of relatively undisturbed constitutional continuity under presidential government-but Chilean democracy broke down in the 1970s.

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Perhaps the most important consequences of the direct relationship that exists between a president and the electorate are the sense the president may have of being the only elected representative of the whole people and the accompanying risk that he will tend to conflate his supporters with "the people" as a whole. The plebiscitarian component implicit in the president's authority is likely to make the obstacles and opposition he encounters seem particularly annoying. In his frustration he may be tempted to define his policies as reflections of the popular will and those of his opponents as the selfish designs of narrow interests. This identification of leader with people fosters a certain populism that may be a source of strength. It may also, however, bring on a refusal to acknowledge the limits of the mandate that even a majority-to say nothing of a mere plurality~an claim as democratic justification for the enactment of its agenda. The doleful potential for displays of cold indifference, disrespect, or even downright hostility toward the opposition is not to be scanted.