Well as I'm sure you know we live in a society greatly impacted by technology and because so everything important usually ends up on the internet, the dissemination of news helps activists and the regular joe, educate themselves. But as in a political revolution starting I suppose dissemination would make them more educated in the debate, and allow them to spread there message.
The immediate cause of World War I that made the aforementioned items come into play (alliances, imperialism, militarism, nationalism) was the assassination of Archduke Franz Ferdinand of Austria-Hungary. When Russia began to mobilize due to its alliance with Serbia, Germany declared war on Russia.
