WWI was a textbook example of the dangers of intertwined alliances.
Dirtboy is right....nail on head
The glory part was to get folks to enlist but it didnt cause the war
Treaties and colonial clashes and Empires friction sparked by a Serbian murder of Austrias Crown Prince and his wife for reasons never completely understood to be honest....free Serbs from Austrian or Ottoman rule?
Anyhow....what really cause WWI was slow communication and travel for dilplomats
Today rushed meetings would likely have averted that craziness
And Europe was no question more accustomed to war