The United States is not ruled by "the people," it is ruled by the rich and high-level bureaucrats. If the workers vote the wrong way the owners will withdraw their investments, causing the economy to crash. Then that party will lose the next election. Usually what happens is the elected representatives abandon the policies that cause the owners to withdraw their investments & adopt policies more favorable to the capitalist class, so that they will not be creamed in the next election. Plus the state bureaucracy can effectively undercut the policies of elected representatives. The CIA has overthrown lots of governments without the knowledge of congress, sometimes even without the knowledge of the President, and could easily do so domestically if the wrong people got elected. In addition, there are added layers of control including the two-party system, the tendency of the police & FBI to suppress any radical leftist party that gets large numbers of votes (the suppression of the Socialist Party USA is a well known example), media bias against radical left candidates, the fact that rich people can more easily win elections since they have more money for advertisements and things of that nature, the "revolving door" between government service & corporate executives, bribery of candidates ("campaign financing") and the dependancy of candidates on the rich for money to run their campaigns.