New research supports the notion that we fixate on enemies, and inflate their power, as a defense mechanism against generalized anxiety.
The longer article is here. This is another way of putting the point:
According to one school of thought, this tendency to exaggerate the strength of our adversaries serves a specific psychological function. It is less scary to place all our fears on a single, strong enemy than to accept the fact our well-being is largely based on factors beyond our control. An enemy, after all, can be defined, analyzed and perhaps even defeated.