Even before there were modern nation-states, political conflicts arose among competing societies or factions of people. Vikings attacked continental European tribes in search of loot, and, later, European explorers landed on foreign shores to claim the resources of indigenous groups. Conflicts also arose among competing groups within individual sovereignties, as evidenced by the bloody French Revolution. Nearly all conflicts in the past and present, however, are spurred by basic desires: the drive to protect or gain territory and wealth, and the need to preserve liberty and autonomy.
Modern-day conflicts are still driven by the desire to gain or protect power and wealth, whether in the form of land and resources or in the form of liberty and autonomy. Internally, groups within the U.S. struggle within the system, by trying to achieve the outcomes they prefer. Political differences over budget issues, for example, led to the recent shutdown of the federal government, and alternative political groups, such as the Tea Party, are gaining a significant following.