Television has transformed politics in the United States by changing the way in which information is disseminated, by altering political campaigns, and by changing citizens' patterns of response to politics. By giving citizens independent access to the candidates, television diminished the role of the political party in the selection of the major party candidates. By centering politics on the person of the candidate, television accelerated the citizen's focus on character than issues. Television has altered the forms of political communication as well. The messages on which most of us rely are briefer than they once were. The stump speech, a political speech given by traveling politicians and lasting 1.5 to 2 hours, which characterized nineteenth century political discourse, has given way to the 30-second advertisement and 10-second 'sound bite (摘要)' in broadcast news. Increasingly the audience for speeches is not that standing in front of the politician but rather viewing audience who will hear and see a snippet (摘录) of the speech on the news. In these abbreviated (缩减的)forms, much of what constituted the traditional political discourse of earlier ages has been lost. In 15 or 30 seconds, a speaker cannot establish the historical context that shaped the issue in question, cannot detail the probable causes of the problem, and cannot examine alternative proposals to argue that one is preferable to others. In snippets, politicians assert but do not argue. Because television is an intimate medium, speaking through it required a changed political style. that was more conversational, personal, and visual than that of the old-style. stump speech. Reliance on television means that increasingly our political world contains memorable pictures rather than memorable words. Schools teach us to analyze words and print. However, in a world in which politics is increasingly visual, informed citizenship requires a new set of skills. Recognizing the power of television's pictures, politicians craft televisual, staged events, called pseudo events, designed to attract media coverage. Much of the political activity we see on television news has been crafted by politicians, their speechwriters, and their public relations advisers for televised consumption bites in news and answers to questions in debates increasingly sound like advertisements. It can be inferred from the passage that ______.