How was militarism a cause of WWI?

First, one of the underlying causes of World War I is imperialism. It was because of this cause which brought nations in Europe to divide. Imperialism was the reason to which countries fought over for more land. This underlying cause made Europe at the brink of war a few times even before 1914 as more countries tried harder to expand their empires. In 1905 and 1911, France and Germany avoided a two-front war with each other over Morocco.

Explanation:

the russian revolution of 1917 involved the collapse of an empire under tsar nicholas ii and the rise of marxian socialism under lenin and his bolsheviks.