What was the cause? The nation itself. The crosses stand as validation of the greatness of each nation for which soldiers had given their lives.

During the First World War, each nation asserted the reality of its own sacred object or ideal. Each nation struggled to demonstrate its superiority--the depth of its devotion--by gifting young men.

The precise nature of the entity to which lives were sacrificed didn’t matter--France, Germany, Great Britain, Italy, Russia, etc.  What was essential was that sacrifices continued to be performed, death affirmed--in the name of the nation-state. 

This was a world war. No nation wished to be left out. It was a family affair. 

How proud human beings are of their world wars, which lie at the heart of the first half of the 20th century. Human beings created these wars to exhibit the depth of their spirituality: their contempt for mundane existence. By engaging in these monumental episodes of destruction or self-destruction, human beings demonstrated their devotion to “sacred objects” that lay at the heart of their societies.