The 20th century is usually referred to as a century of "war and revolution" that brought unprecedented bloodshed and misery. While this is true, the description is not sufficiently accurate. During the religious wars of the 17th century, for example, Germany, as the main battlefield, lost an estimated 30 percent to 40 percent of its population as a result of wars among states coupled with religious ideological conflicts. In contrast, the World War II death toll for the Soviet Union, which suffered the most fatalities, represented about 10 percent of the country's total population.
What was unprecedented about the 20th century is that it saw "world" wars and "world" revolutions. Not only the two world wars but the Cold War too was a global confrontation. In addition, the West viewed the many revolutions as a challenge from "world" communism. In the 20th century we had already entered the age of "globalization" through war and revolution.
But because the century was characterized by division and confrontation brought on by the wars and revolutions, it was perceived to consist of "Two Worlds," "Two Blocs" and "Two Universal Ideologies." In reality, people were confronting each other globally over their perceptions of what the world should be like.